Ejemplo n.º 1
0
def imarith(operand1, op, operand2, result):
    info("%s %s %s -> %s" % (operand1, op, operand2, result))
    assert type(operand1) == str
    assert type(operand2) == str
    assert os.path.exists(operand1)
    assert os.path.exists(operand2)
    assert op in ['+', '-']

    ## Strip off the [0] part of the operand as we are assuming that we are
    ## operating on the 0th FITS HDU.
    if re.match('(\w+\.fits)\[0\]', operand1):
        operand1 = operand1[:-3]
    if re.match('(\w+\.fits)\[0\]', operand2):
        operand2 = operand2[:-3]

    import operator
    operation = { "+": operator.add, "-": operator.sub,\
                  "*": operator.mul, "/": operator.truediv}

    hdulist1 = pf.open(operand1, 'readonly')
    hdulist2 = pf.open(operand2, 'readonly')
    data = operation[op](hdulist1[0].data, hdulist2[0].data)
    header = hdulist1[0].header
    header['history'] = 'imarith {} {} {}'.format(operand1, op, operand2)
    header['history'] = 'Header values copied from {}'.format(operand1)
    if 'EXPTIME' in hdulist1[0].header and\
       'EXPTIME' in hdulist2[0].header and\
       operation in ['+', '-']:
        exptime = operation[op](float(hdulist1[0].header['EXPTIME']),\
                                float(hdulist2[0].header['EXPTIME']))
        header['history'] = 'Other than exposure time which was edited'
        header['EXPTIME'] = exptime

    hdu = pf.PrimaryHDU(data=data, header=header)
    hdu.writeto(result)
Ejemplo n.º 2
0
def imcombine(filelist,
              out,
              options,
              bpmask=None,
              reject="none",
              nlow=None,
              nhigh=None):
    '''Convenience wrapper around IRAF task imcombine

    Args:
        filelist: The list of files to imcombine
        out: The full path to the output file
        options: Options dictionary
        bpmask: The full path to the bad pixel mask
        reject: none, minmax, sigclip, avsigclip, pclip
        nlow,nhigh: Parameters for minmax rejection, see iraf docs
    
    Returns:
        None

    Side effects:
        Creates the imcombined file at location `out'
    '''

    #TODO: REMOVE Iraf and use python instead. STSCI Python has
    # A builtin routine.
    from pyraf import iraf
    iraf.images()

    filelist = [("%s[0]" % f) for f in filelist]
    pars = iraf.imcombine.getParList()
    iraf.imcombine.unlearn()

    path = "flatcombine.lst"
    f = open(path, "w")
    for file in filelist:
        f.write(file + "\n")
    f.close()

    s = ("%s," * len(filelist))[0:-1]
    s = s % tuple(filelist)

    f = open("flatcombinelog.txt", "w")
    if reject == 'minmax':
        t = iraf.imcombine("@%s" % path,
                           out,
                           Stdout=f,
                           reject=reject,
                           nlow=nlow,
                           nhigh=nhigh)
    else:
        t = iraf.imcombine(s, out, Stdin=filelist, Stdout=f, reject=reject)
    f.close()
    f = open("flatcombinelog.txt")
    for line in f:
        info(line.rstrip("\n"))
    f.close()

    iraf.imcombine.setParList(pars)
Ejemplo n.º 3
0
def fix_long2pos_headers(filelist):
    '''Fixes old long2pos observations which have a wrong set of keywords'''
    files = list_file_to_strings(filelist)
    # Print the filenames to Standard-out
    info("Fixing long2pos headers for files in " + str(filelist))

    # Iterate through files
    for fname in files:
        if os.path.isabs(fname): path = fname
        else: path = os.path.join(fname_to_path(fname, options), fname)

        hdulist = pf.open(path, mode='update')
        header = hdulist[0].header

        #determine if this file really needs to be updated (for example, prevents a second update of an already updated file
        if 'long2pos' in header['MASKNAME'] and header[
                'FRAMEID'] == 'object' and (header['PATTERN'] == 'long2pos'
                                            or header['PATTERN'] == 'Stare'):
            info("File " + str(fname) + " will be updated")

            # make a copy of the original file
            newname = path + ".original"
            info("copying ... " + str(path))
            info("into ...... " + str(newname))
            shutil.copyfile(path, newname)
            if not os.path.exists(newname):
                error(
                    "Error in generating original file:  '%s' does not exist (could not be created)."
                    % newname)
                raise Exception(
                    "Error in generating original file:  '%s' does not exist (could not be created)."
                    % newname)

            #updating header
            # assign FRAMEID to narrow slits
            if header['YOFFSET'] == 21 or header['YOFFSET'] == -7:
                header['FRAMEID'] = "B"
            if header['YOFFSET'] == -21 or header['YOFFSET'] == 7:
                header['FRAMEID'] = "A"

            # assign FRAMEID to wide slits
            if header['YOFFSET'] == 14 or header['YOFFSET'] == -14:
                header['FRAMEID'] = "A"

            #reverse sign of offsets for narrow slits
            if header['YOFFSET'] == -21:
                header['YOFFSET'] = 7
            if header['YOFFSET'] == 21:
                header['YOFFSET'] = -7

            #transform Xoffset from pixels to arcseconds
            header['XOFFSET'] = header['XOFFSET'] * 0.18
        else:
            info("File " + str(fname) + " does not need to be updated")
        hdulist.flush()
        hdulist.close()
Ejemplo n.º 4
0
    def set_header(self, header, ssl=None, msl=None, asl=None, targs=None):
        '''Passed "header" a FITS header dictionary and converts to a Barset'''
        self.pos = np.array(IO.parse_header_for_bars(header))
        self.set_pos_pix()

        self.ssl = ssl
        self.msl = msl
        self.asl = asl
        self.targs = targs

        def is_alignment_slit(slit):
            return (np.float(slit["Target_Priority"]) < 0)

        # If len(ssl) == 0 then the header is for a long slit
        if (header['MASKNAME'] == 'long2pos') or (header['MASKNAME'] == 'long2pos_specphot'):
            info("long2pos mode in CSU slit determination")
            self.long2pos_slit = True

        if (len(ssl) == 0):
        
            self.long_slit = True

            start = np.int(msl[0]["Slit_Number"])
            stop = np.int(msl[-1]["Slit_Number"])


            for mech_slit in msl:
                mech_slit["Target_in_Slit"] = "long"

            self.ssl = np.array([("1", "??", "??", "??", "??", "??", "??", msl[0]['Slit_width'],
                (stop-start+1)*7.6, "0", "long", "0")],
                dtype= [ ('Slit_Number', '|S2'), 
                ('Slit_RA_Hours', '|S2'), ('Slit_RA_Minutes', '|S2'), ('Slit_RA_Seconds', '|S5'),
                ('Slit_Dec_Degrees', '|S3'), ('Slit_Dec_Minutes', '|S2'), ('Slit_Dec_Seconds', '|S5'), 
                ('Slit_width', '|S5'), ('Slit_length', '|S5'), ('Target_to_center_of_slit_distance', '|S5'), 
                ('Target_Name', '|S80'), ('Target_Priority', '|S1')])
            self.scislit_to_slit = [ np.arange(start,stop) ]
            ssl = None

        # Create a map between scislit number and mechanical slit
        # recall that slits count from 1
        if ssl is not None:
            prev = self.msl[0]["Target_in_Slit"]

            v = []

            for science_slit in ssl:
                targ = science_slit["Target_Name"]
                v.append([int(x) for x in self.msl.field("Slit_Number")[np.where(self.msl.Target_in_Slit == targ)[0]]])
            self.scislit_to_slit = v

            if (len(self.scislit_to_slit) != len(ssl)) and not (self.long_slit
                    and len(self.scislit_to_slit) == 1):
                error("SSL should match targets in slit")
                raise Exception("SSL should match targets in slit")
Ejemplo n.º 5
0
def imarith(operand1, op, operand2, result):
    from pyraf import iraf
    iraf.images()

    pars = iraf.imarith.getParList()
    iraf.imcombine.unlearn()

    info("%s %s %s -> %s" % (operand1, op, operand2, result))
    iraf.imarith(operand1=operand1, op=op, operand2=operand2, result=result)

    iraf.imarith.setParList(pars)
Ejemplo n.º 6
0
def imarith(operand1, op, operand2, result):
    from pyraf import iraf
    iraf.images()

    pars = iraf.imarith.getParList()
    iraf.imcombine.unlearn()

    info( "%s %s %s -> %s" % (operand1, op, operand2, result))
    iraf.imarith(operand1=operand1, op=op, operand2=operand2, result=result)

    iraf.imarith.setParList(pars)
Ejemplo n.º 7
0
def writefits(img, maskname, fname, options, header=None, bs=None,
        overwrite=False, lossy_compress=False):
    '''Convenience wrapper to write MOSFIRE drp-friendly FITS files
    
    Args:
        img: Data array to write to disk
        maskname: Name of the science mask
        fname: Full or relative path to output file
        options: {} Unused
        header: Optional, the header to write
        bs: Optional unused
        overwrite: Force overwrite of file, default False/No.
        lossy_compress: Zero out the lowest order bits of the floats in
            order to make FITS files amenable to compression. The loss is
            at least 10 x less than 5e- which is the lowest reasonable read-
            noise value.

    Results:
        Writes a file to fname with data img and header header.

    '''

    if lossy_compress:
        hdu = pf.PrimaryHDU(floatcompress(img))
    else:
        hdu = pf.PrimaryHDU(img)

    fn = fname

    if header is None: header = {"DRPVER": (MOSFIRE.__version__, "DRP Version Date")}
    else: header["DRPVER"] = (MOSFIRE.__version__, 'DRP Version Date')

    warnings.filterwarnings('ignore')
    if header is not None:
        for k,value, comment in header.cards:
            if k in hdu.header: continue

            if k == 'COMMENT': continue
            if k == '': continue

            k = k.rstrip()
            hdu.header[k] = (value,comment)

    warnings.filterwarnings('always')
    if overwrite:
        try: 
            os.remove(fn)
            info("Removed old file '{0}'%".format(fn))
        except: pass

    info("Wrote to '%s'" % (fn))
    hdu.writeto(fn)

    if lossy_compress: os.system("gzip --force {0}".format(fn))
Ejemplo n.º 8
0
def imcombine(filelist, out, options, bpmask=None, reject="none", nlow=None,
        nhigh=None):

    '''Convenience wrapper around IRAF task imcombine

    Args:
        filelist: The list of files to imcombine
        out: The full path to the output file
        options: Options dictionary
        bpmask: The full path to the bad pixel mask
        reject: none, minmax, sigclip, avsigclip, pclip
        nlow,nhigh: Parameters for minmax rejection, see iraf docs
    
    Returns:
        None

    Side effects:
        Creates the imcombined file at location `out'
    '''

    #TODO: REMOVE Iraf and use python instead. STSCI Python has
    # A builtin routine.
    from pyraf import iraf
    iraf.images()


    filelist = [("%s[0]" % f) for f in filelist]
    pars = iraf.imcombine.getParList()
    iraf.imcombine.unlearn()

    path = "flatcombine.lst"
    f = open(path, "w")
    for file in filelist:
        f.write(file + "\n")
    f.close()

    s = ("%s," * len(filelist))[0:-1]
    s = s % tuple(filelist)

    f = open("flatcombinelog.txt", "w")
    if reject == 'minmax':
        t = iraf.imcombine("@%s" % path, out, Stdout=f,
            reject=reject, nlow=nlow, nhigh=nhigh)
    else:
        t = iraf.imcombine(s, out, Stdin=filelist, Stdout=f,
            reject=reject)
    f.close()
    f=open("flatcombinelog.txt")
    for line in f:
        info(line.rstrip("\n"))
    f.close()

    iraf.imcombine.setParList(pars)
Ejemplo n.º 9
0
    def test_lhs_v_rhs(self):
        sa = self.assertTrue

        p0 = [0.5, 5, 1.1,.7,0]
        pn0 = [0.5, 5, -1.1,.7,0]
        xs = np.arange(25)
        ys = fit_single(p0, xs)
        lsf = do_fit(ys, residual_single)
        info(str(lsf[0]))

        ys = fit_single(pn0, xs)
        lsf = do_fit(ys, residual_single)
        info(str(lsf[0]))
Ejemplo n.º 10
0
    def test_lhs_v_rhs(self):
        sa = self.assertTrue

        p0 = [0.5, 5, 1.1, .7, 0]
        pn0 = [0.5, 5, -1.1, .7, 0]
        xs = np.arange(25)
        ys = fit_single(p0, xs)
        lsf = do_fit(ys, residual_single)
        info(str(lsf[0]))

        ys = fit_single(pn0, xs)
        lsf = do_fit(ys, residual_single)
        info(str(lsf[0]))
Ejemplo n.º 11
0
def fix_long2pos_headers(filelist):
    '''Fixes old long2pos observations which have a wrong set of keywords'''
    files = list_file_to_strings(filelist)
    # Print the filenames to Standard-out
    info("Fixing long2pos headers for files in "+str(filelist))

    # Iterate through files
    for fname in files:
        if os.path.isabs(fname): path = fname
        else: path = os.path.join(fname_to_path(fname, options), fname)

        hdulist = pf.open(path, mode='update')
        header = hdulist[0].header

        #determine if this file really needs to be updated (for example, prevents a second update of an already updated file
        if 'long2pos' in header['MASKNAME'] and header['FRAMEID']=='object' and (header['PATTERN']=='long2pos' or header['PATTERN']=='Stare'):
            info( "File "+str(fname)+" will be updated")

            # make a copy of the original file
            newname = path+".original"
            info("copying ... "+str(path))
            info("into ...... "+str(newname))
            shutil.copyfile(path,newname)
            if not os.path.exists(newname):
                error("Error in generating original file:  '%s' does not exist (could not be created)." % newname)
                raise Exception("Error in generating original file:  '%s' does not exist (could not be created)." % newname)            

            #updating header
            # assign FRAMEID to narrow slits
            if header['YOFFSET']==21 or header['YOFFSET']==-7:
                header['FRAMEID']="B"
            if header['YOFFSET']==-21 or header['YOFFSET']==7:
                header['FRAMEID']="A"

            # assign FRAMEID to wide slits
            if header['YOFFSET']==14 or header['YOFFSET']==-14:
                header['FRAMEID']="A"
                
            #reverse sign of offsets for narrow slits
            if header['YOFFSET']==-21:
                header['YOFFSET']=7
            if header['YOFFSET']==21:
                header['YOFFSET']=-7

            #transform Xoffset from pixels to arcseconds
            header['XOFFSET'] = header['XOFFSET']*0.18
        else:
            info("File "+str(fname)+" does not need to be updated")
        hdulist.flush()
        hdulist.close()
Ejemplo n.º 12
0
def list_file_to_strings(fname):
    '''Read the filename in fname and convert to a series of paths.
This emulates IRAF's @file system. However, in addtion, the first line of the file
can be an absolute path. Example:
list.txt
/path/to/files
file1
file2
file3

returns ['/path/to/files/file1', '/path/to/files/file2', '/path/to/files/file3']

whereas
list.txt
file1
file2
file3

returns ['file1', 'file2', 'file3']
'''

    filelist = fname
    if type(fname) == str:
        filelist = [fname]

    if len(fname) == 0:
        return []

    if fname[0][-5:] == '.fits':
        return fname

    output = []

    for fname in filelist:
        info("Loading: %s" % fname)
        inputs = np.loadtxt(fname, dtype=[("f", "S100")])
        path = ""
        start_index = 0
        if len(inputs):
            if os.path.isabs(inputs[0][0]):
                path = inputs[0][0]
                start_index = 1

            for i in xrange(start_index, len(inputs)):
                output.append(os.path.join(path, inputs[i][0]))

    return output
Ejemplo n.º 13
0
def list_file_to_strings(fname):
    '''Read the filename in fname and convert to a series of paths.
This emulates IRAF's @file system. However, in addtion, the first line of the file
can be an absolute path. Example:
list.txt
/path/to/files
file1
file2
file3

returns ['/path/to/files/file1', '/path/to/files/file2', '/path/to/files/file3']

whereas
list.txt
file1
file2
file3

returns ['file1', 'file2', 'file3']
'''

    filelist = fname
    if type(fname) == str:
        filelist = [fname]

    if len(fname) == 0:
        return []

    if fname[0][-5:] == '.fits':
        return fname

    output = []

    for fname in filelist:
        info( "Loading: %s" % fname)
        inputs = np.loadtxt(fname, dtype= [("f", "S100")])
        path = ""
        start_index = 0
        if len(inputs):
            if os.path.isabs(inputs[0][0]):
                path = inputs[0][0]
                start_index = 1

            for i in xrange(start_index, len(inputs)):
                output.append(os.path.join(path, inputs[i][0]))

    return output
Ejemplo n.º 14
0
def fit_edge_poly(xposs, xposs_missing, yposs, order):
    '''
    fit_edge_poly fits a polynomial to the measured slit edges.
    This polynomial is used to extract spectra.

    fit_edge_poly computes a parabola, and fills in missing data with a 
    parabola

    input-
    xposs, yposs [N]: The x and y positions of the slit edge [pix]
    order: the polynomial order
    '''

    # First fit low order polynomial to fill in missing data
    fun = np.poly1d(Fit.polyfit_clip(xposs, yposs, 2))

    xposs = np.append(xposs, xposs_missing)
    yposs = np.append(yposs, fun(xposs_missing))

    # Remove any fits that deviate wildly from the 2nd order polynomial
    ok = np.abs(yposs - fun(xposs)) < 1
    if not ok.any():
            error("Flat is not well illuminated? Cannot find edges")
            raise Exception("Flat is not well illuminated? Cannot find edges")

    # Now refit to user requested order
    fun = np.poly1d(Fit.polyfit_clip(xposs[ok], yposs[ok], order))
    res = fun(xposs[ok]) - yposs[ok]
    sd = np.std(res)
    ok = np.abs(res) < 2*sd


    # Check to see if the slit edge funciton is sane, 
    # if it's not, then we fix it.
    pix = np.arange(2048)
    V = fun(pix)
    if np.abs(V.max() - V.min()) > 10:
        info ("Forcing a horizontal slit edge")
        print "Forcing a horizontal slit edge"
        fun = np.poly1d(np.median(yposs[ok]))


    return (fun, res, sd, ok)
Ejemplo n.º 15
0
def fit_edge_poly(xposs, xposs_missing, yposs, order):
    '''
    fit_edge_poly fits a polynomial to the measured slit edges.
    This polynomial is used to extract spectra.

    fit_edge_poly computes a parabola, and fills in missing data with a 
    parabola

    input-
    xposs, yposs [N]: The x and y positions of the slit edge [pix]
    order: the polynomial order
    '''

    # First fit low order polynomial to fill in missing data
    fun = np.poly1d(Fit.polyfit_clip(xposs, yposs, 2))

    xposs = np.append(xposs, xposs_missing)
    yposs = np.append(yposs, fun(xposs_missing))

    # Remove any fits that deviate wildly from the 2nd order polynomial
    ok = np.abs(yposs - fun(xposs)) < 1
    if not ok.any():
            error("Flat is not well illuminated? Cannot find edges")
            raise Exception("Flat is not well illuminated? Cannot find edges")

    # Now refit to user requested order
    fun = np.poly1d(Fit.polyfit_clip(xposs[ok], yposs[ok], order))
    res = fun(xposs[ok]) - yposs[ok]
    sd = np.std(res)
    ok = np.abs(res) < 2*sd


    # Check to see if the slit edge funciton is sane, 
    # if it's not, then we fix it.
    pix = np.arange(2048)
    V = fun(pix)
    if np.abs(V.max() - V.min()) > 10:
        info ("Forcing a horizontal slit edge")
        print "Forcing a horizontal slit edge"
        fun = np.poly1d(np.median(yposs[ok]))


    return (fun, res, sd, ok)
Ejemplo n.º 16
0
def find_edge_pair(data, y, roi_width, edgeThreshold=450):
    '''
    find_edge_pair finds the edge of a slit pair in a flat

    data[2048x2048]: a well illuminated flat field [DN]
    y: guess of slit edge position [pix]

    Keywords:
    
    edgeThreshold: the pixel value below which we should ignore using
    to calculate edges.
    
    Moves along the edge of a slit image
            - At each location along the slit edge, determines
            the position of the demarcations between two slits

    Outputs:
    xposs []: Array of x positions along the slit edge [pix]
    yposs []: The fitted y positions of the "top" edge of the slit [pix]
    widths []: The fitted delta from the top edge of the bottom [pix]
    scatters []: The amount of light between slits


    The procedure is as follows
    1: starting from a guess spatial position (parameter y), march
        along the spectral direction in some chunk of pixels
    2: At each spectral location, construct a cross cut across the
        spatial direction; select_roi is used for this.
    3: Fit a two-sided error function Fit.residual_disjoint_pair
        on the vertical cross cut derived in step 2.
    4: If the fit fails, store it in the missing list
        - else if the top fit is good, store the top values in top vector
        - else if the bottom fit is good, store the bottom values in bottom
          vector.
    5: In the vertical cross-cut, there is a minimum value. This minimum
        value is stored as a measure of scattered light.

    Another procedure is used to fit polynomials to these fitted values.
    '''

    def select_roi(data, roi_width):
        v = data[y-roi_width:y+roi_width, xp-2:xp+2]
        v = np.median(v, axis=1) # Axis = 1 is spatial direction

        return v



    xposs_top = []
    yposs_top = []
    xposs_top_missing = []

    xposs_bot = []
    yposs_bot = []
    xposs_bot_missing = []
    yposs_bot_scatters = []

    #1 
    rng = np.linspace(10, 2040, 50).astype(np.int)
    for i in rng:
        xp = i
        #2
        v = select_roi(data, roi_width)
        xs = np.arange(len(v))

        # Modified from 450 as the hard coded threshold to one that
        # can be controlled by a keyword
        if (np.median(v) < edgeThreshold):
            xposs_top_missing.append(xp)
            xposs_bot_missing.append(xp)
            continue

        #3
        ff = Fit.do_fit(v, residual_fun=Fit.residual_disjoint_pair)
        fit_ok = 0 < ff[4] < 4

        if fit_ok:
            (sigma, offset, mult1, mult2, add, width) = ff[0]

            xposs_top.append(xp)
            yposs_top.append(y - roi_width + offset + width)

            xposs_bot.append(xp)
            yposs_bot.append(y - roi_width + offset)

            between = offset + width/2
            if 0 < between < len(v)-1:
                start = np.max([0, between-2])
                stop = np.min([len(v),between+2])
                yposs_bot_scatters.append(np.min(v[start:stop])) # 5

                if False:
                    pl.figure(2)
                    pl.clf()
                    tmppix = np.arange(y-roi_width, y+roi_width)
                    tmpx = np.arange(len(v))
                    pl.axvline(y - roi_width + offset + width, color='red')
                    pl.axvline(y - roi_width + offset, color='red')
                    pl.scatter(tmppix, v)
                    pl.plot(tmppix, Fit.fit_disjoint_pair(ff[0], tmpx))
                    pl.axhline(yposs_bot_scatters[-1])
                    pl.draw()

            else:
                yposs_bot_scatters.append(np.nan)

        else:
            xposs_bot_missing.append(xp)
            xposs_top_missing.append(xp)
            info("Skipping wavelength pixel): %i" % (xp))

    
    return map(np.array, (xposs_bot, xposs_bot_missing, yposs_bot, xposs_top,
        xposs_top_missing, yposs_top, yposs_bot_scatters))
Ejemplo n.º 17
0
def imcombine(filelist, out, options, method="average", reject="none",\
              lsigma=3, hsigma=3, mclip=False,\
              nlow=None, nhigh=None):
    '''Combines images in input list with optional rejection algorithms.

    Args:
        filelist: The list of files to imcombine
        out: The full path to the output file
        method: either "average" or "median" combine
        options: Options dictionary
        bpmask: The full path to the bad pixel mask
        reject: none, minmax, sigclip
        nlow,nhigh: Parameters for minmax rejection, see iraf docs
        mclip: use median as the function to calculate the baseline values for
               sigclip rejection?
        lsigma, hsigma: low and high sigma rejection thresholds.
    
    Returns:
        None

    Side effects:
        Creates the imcombined file at location `out'
    '''
    assert method in ['average', 'median']
    if os.path.exists(out):
        os.remove(out)

    if reject == 'none':
        info('Combining files using ccdproc.combine task')
        info('  reject=none')
        for file in filelist:
            debug('  Combining: {}'.format(file))
        ccdproc.combine(filelist, out, method=method,\
                        minmax_clip=False,\
                        iraf_minmax_clip=True,\
                        sigma_clip=False,\
                        unit="adu")
        info('  Done.')
    elif reject == 'minmax':
        ## The IRAF imcombine minmax rejection behavior is different than the
        ## ccdproc minmax rejection behavior.  We are using the IRAF like
        ## behavior here.  To support this a pull request for the ccdproc
        ## package has been made:
        ##    https://github.com/astropy/ccdproc/pull/358
        ##
        ## Note that the ccdproc behavior still differs slightly from the
        ## nominal IRAF behavior in that the rejection does not consider whether
        ## any of the rejected pixels have been rejected for other reasons, so
        ## if nhigh=1 and that pixel was masked for some other reason, the
        ## new ccdproc algorithm, will not mask the next highest pixel, it will
        ## still just mask the highest pixel even if it is already masked.
        ##
        ## From IRAF (help imcombine):
        ##  nlow = 1,  nhigh = 1 (minmax)
        ##      The number of  low  and  high  pixels  to  be  rejected  by  the
        ##      "minmax"  algorithm.   These  numbers are converted to fractions
        ##      of the total number of input images so  that  if  no  rejections
        ##      have  taken  place  the  specified number of pixels are rejected
        ##      while if pixels have been rejected by masking, thresholding,  or
        ##      non-overlap,   then   the  fraction  of  the  remaining  pixels,
        ##      truncated to an integer, is used.
        ##

        ## Check that minmax rejection is possible given the number of images
        if nlow is None:
            nlow = 0
        if nhigh is None:
            nhigh = 0
        if nlow + nhigh >= len(filelist):
            warning(
                'nlow + nhigh >= number of input images.  Combining without rejection'
            )
            nlow = 0
            nhigh = 0

        if ccdproc.version.major >= 1 and ccdproc.version.minor >= 1\
           and ccdproc.version.release:
            info('Combining files using ccdproc.combine task')
            info('  reject=clip_extrema')
            info('  nlow={}'.format(nlow))
            info('  nhigh={}'.format(nhigh))
            for file in filelist:
                info('  {}'.format(file))
            ccdproc.combine(filelist, out, method=method,\
                            minmax_clip=False,\
                            clip_extrema=True,\
                            nlow=nlow, nhigh=nhigh,\
                            sigma_clip=False,\
                            unit="adu")
            info('  Done.')
        else:
            ## If ccdproc does not have new rejection algorithm in:
            ## https://github.com/astropy/ccdproc/pull/358
            ## Manually perform rejection using ccdproc.combiner.Combiner object
            info(
                'Combining files using local clip_extrema rejection algorithm')
            info('and the ccdproc.combiner.Combiner object.')
            info('  reject=clip_extrema')
            info('  nlow={}'.format(nlow))
            info('  nhigh={}'.format(nhigh))
            for file in filelist:
                info('  {}'.format(file))
            ccdlist = []
            for file in filelist:
                ccdlist.append(ccdproc.CCDData.read(file, unit='adu', hdu=0))
            c = ccdproc.combiner.Combiner(ccdlist)
            nimages, nx, ny = c.data_arr.mask.shape
            argsorted = np.argsort(c.data_arr.data, axis=0)
            mg = np.mgrid[0:nx, 0:ny]
            for i in range(-1 * nhigh, nlow):
                where = (argsorted[i, :, :].ravel(), mg[0].ravel(),
                         mg[1].ravel())
                c.data_arr.mask[where] = True
            if method == 'average':
                result = c.average_combine()
            elif method == 'median':
                result = c.median_combine()
            for key in ccdlist[0].header.keys():
                header_entry = ccdlist[0].header[key]
                if key != 'COMMENT':
                    result.header[key] = (header_entry,
                                          ccdlist[0].header.comments[key])
            hdul = result.to_hdu()
            #             print(hdul)
            #             for hdu in hdul:
            #                 print(type(hdu.data))
            hdul[0].writeto(out)
            #             result.write(out)
            info('  Done.')
    elif reject == 'sigclip':
        info('Combining files using ccdproc.combine task')
        info('  reject=sigclip')
        info('  mclip={}'.format(mclip))
        info('  lsigma={}'.format(lsigma))
        info('  hsigma={}'.format(hsigma))
        baseline_func = {False: np.mean, True: np.median}
        ccdproc.combine(filelist, out, method=method,\
                        minmax_clip=False,\
                        clip_extrema=False,\
                        sigma_clip=True,\
                        sigma_clip_low_thresh=lsigma,\
                        sigma_clip_high_thresh=hsigma,\
                        sigma_clip_func=baseline_func[mclip],\
                        sigma_clip_dev_func=np.std,\
                        )
        info('  Done.')
    else:
        raise NotImplementedError(
            '{} rejection unrecognized by MOSFIRE DRP'.format(reject))
Ejemplo n.º 18
0
def make_pixel_flat(data, results, options, outfile, inputs, lampsOff=None):
    '''
    Convert a flat image into a flat field
    '''

    def pixel_min(y): return np.floor(np.min(y))
    def pixel_max(y): return np.ceil(np.max(y))

    def collapse_flat_box(dat):
        '''Collapse data to the spectral axis (0)'''
        v = np.median(dat, axis=0).ravel()

        return v

    flat = np.ones(shape=Detector.npix)

    hdu = pyfits.PrimaryHDU((data/flat).astype(np.float32))
    hdu.header.update("version", __version__, "DRP version")
    i = 0
    for flatname in inputs:
        nm = flatname.split("/")[-1]
        hdu.header.update("infile%2.2i" % i, nm)
        i += 1

    slitno = 0
    for result in results[0:-1]:
        slitno += 1

        hdu.header.update("targ%2.2i" % slitno, result["Target_Name"])

        bf = result["bottom"]
        tf = result["top"]
        try:
            hpps = result["hpps"]
        except:
            error( "No half power points for this slit")
            hpps = [0, Detector.npix[0]]

        xs = np.arange(hpps[0], hpps[1])

        top = pixel_min(tf(xs))
        bottom = pixel_max(bf(xs))

        hdu.header.update("top%2.2i" % slitno, top)
        hdu.header.update("bottom%2.2i" % slitno, bottom)

        info( "%s] Bounding top/bottom: %i/%i" % (result["Target_Name"],
                bottom, top))

        v = collapse_flat_box(data[bottom:top,hpps[0]:hpps[1]])

        x2048 = np.arange(Options.npix)
        v = np.poly1d(np.polyfit(xs,v,
            options['flat-field-order']))(xs).ravel()

        for i in np.arange(bottom-1, top+1):
            flat[i,hpps[0]:hpps[1]] = v

    info( "Producing Pixel Flat...")
    for r in range(len(results)-1):
        theslit = results[r]

        try:
            bf = theslit["bottom"]
            tf = theslit["top"]
        except:
            pdb.set_trace()

        for i in range(hpps[0], hpps[1]):
            top = np.floor(tf(i))
            bottom = np.ceil(bf(i))
            
            data[top:bottom, i] = flat[top:bottom,i]

    hdu.data = (data/flat).astype(np.float32)
    bad = np.abs(hdu.data-1.0) > 0.5
    hdu.data[bad] = 1.0
    hdu.data = hdu.data.filled(1)
    if os.path.exists(outfile):
            os.remove(outfile)
    hdu.writeto(outfile)
Ejemplo n.º 19
0
def find_edge_pair(data, y, roi_width, edgeThreshold=450):
    '''
    find_edge_pair finds the edge of a slit pair in a flat

    data[2048x2048]: a well illuminated flat field [DN]
    y: guess of slit edge position [pix]

    Keywords:
    
    edgeThreshold: the pixel value below which we should ignore using
    to calculate edges.
    
    Moves along the edge of a slit image
            - At each location along the slit edge, determines
            the position of the demarcations between two slits

    Outputs:
    xposs []: Array of x positions along the slit edge [pix]
    yposs []: The fitted y positions of the "top" edge of the slit [pix]
    widths []: The fitted delta from the top edge of the bottom [pix]
    scatters []: The amount of light between slits


    The procedure is as follows
    1: starting from a guess spatial position (parameter y), march
        along the spectral direction in some chunk of pixels
    2: At each spectral location, construct a cross cut across the
        spatial direction; select_roi is used for this.
    3: Fit a two-sided error function Fit.residual_disjoint_pair
        on the vertical cross cut derived in step 2.
    4: If the fit fails, store it in the missing list
        - else if the top fit is good, store the top values in top vector
        - else if the bottom fit is good, store the bottom values in bottom
          vector.
    5: In the vertical cross-cut, there is a minimum value. This minimum
        value is stored as a measure of scattered light.

    Another procedure is used to fit polynomials to these fitted values.
    '''
    def select_roi(data, roi_width):
        v = data[y - roi_width:y + roi_width, xp - 2:xp + 2]
        v = np.median(v, axis=1)  # Axis = 1 is spatial direction

        return v

    xposs_top = []
    yposs_top = []
    xposs_top_missing = []

    xposs_bot = []
    yposs_bot = []
    xposs_bot_missing = []
    yposs_bot_scatters = []

    #1
    rng = np.linspace(10, 2040, 50).astype(np.int)
    for i in rng:
        xp = i
        #2
        v = select_roi(data, roi_width)
        xs = np.arange(len(v))

        # Modified from 450 as the hard coded threshold to one that
        # can be controlled by a keyword
        if (np.median(v) < edgeThreshold):
            xposs_top_missing.append(xp)
            xposs_bot_missing.append(xp)
            continue

        #3
        ff = Fit.do_fit(v, residual_fun=Fit.residual_disjoint_pair)
        fit_ok = 0 < ff[4] < 4

        if fit_ok:
            (sigma, offset, mult1, mult2, add, width) = ff[0]

            xposs_top.append(xp)
            yposs_top.append(y - roi_width + offset + width)

            xposs_bot.append(xp)
            yposs_bot.append(y - roi_width + offset)

            between = offset + width / 2
            if 0 < between < len(v) - 1:
                start = np.max([0, between - 2])
                stop = np.min([len(v), between + 2])
                yposs_bot_scatters.append(np.min(v[start:stop]))  # 5

                if False:
                    pl.figure(2)
                    pl.clf()
                    tmppix = np.arange(y - roi_width, y + roi_width)
                    tmpx = np.arange(len(v))
                    pl.axvline(y - roi_width + offset + width, color='red')
                    pl.axvline(y - roi_width + offset, color='red')
                    pl.scatter(tmppix, v)
                    pl.plot(tmppix, Fit.fit_disjoint_pair(ff[0], tmpx))
                    pl.axhline(yposs_bot_scatters[-1])
                    pl.draw()

            else:
                yposs_bot_scatters.append(np.nan)

        else:
            xposs_bot_missing.append(xp)
            xposs_top_missing.append(xp)
            info("Skipping wavelength pixel): %i" % (xp))

    return map(np.array, (xposs_bot, xposs_bot_missing, yposs_bot, xposs_top,
                          xposs_top_missing, yposs_top, yposs_bot_scatters))
Ejemplo n.º 20
0
def handle_background(filelist, wavename, maskname, band_name, options, shifts=None, plan=None, extension=None, target='default'): 
    '''
    Perform difference imaging and subtract residual background.

    The plan looks something like: [['A', 'B']]
    In this case, the number of output files is equal to the length of the list (1).

    If you choose to use an ABA'B' pattern then the plan will be: [["A", "B"], ["A'", "B'"]]
    the background subtraction code will make and handle two files, "A-B" and "A'-B'".
    '''
    
    global header, bs, edges, data, Var, itime, lam, sky_sub_out, sky_model_out, band

    band = band_name

    flatname = "pixelflat_2d_%s.fits" % band_name
    hdr, flat = IO.readfits("pixelflat_2d_%s.fits" % (band_name), options)

    if np.abs(np.median(flat) - 1) > 0.1:
        error("Flat seems poorly behaved.")
        raise Exception("Flat seems poorly behaved.")

    '''
        This next section of the code figures out the observing plan
        and then deals with the bookeeping of sending the plan
        to the background subtracter.
    '''

    hdrs = []
    epss = {}
    vars = {}
    bss = []
    times = {}
    Nframes = []

    i = 0
    header = pf.Header()
    for i in xrange(len(filelist)):
        fl = filelist[i]
        files = IO.list_file_to_strings(fl)
        info("Combining")
        if shifts is None: shift = None
        else: shift = shifts[i]
        hdr, electron, var, bs, time, Nframe = imcombine(files, maskname,
            options, flat, outname="%s.fits" % (fl),
            shifts=shift, extension=extension)

        hdrs.append(hdr) 
        header = merge_headers(header, hdr)
        epss[hdr['FRAMEID']] = electron/time
        vars[hdr['FRAMEID']] = var
        times[hdr['FRAMEID']] = time
        bss.append(bs)
        Nframes.append(Nframe)

    positions = {}
    i = 0
    for h in hdrs:
        positions[h['FRAMEID']] = i
        i += 1
    posnames = set(positions.keys())
    if plan is None:
        plan = guess_plan_from_positions(posnames)

    num_outputs = len(plan)


    edges, meta = IO.load_edges(maskname, band, options)
    lam = IO.readfits(wavename, options)

    bs = bss[0]

    for i in xrange(num_outputs):
        posname0 = plan[i][0]
        posname1 = plan[i][1]
        info("Handling %s - %s" % (posname0, posname1))
        data = epss[posname0] - epss[posname1]
        Var = vars[posname0] + vars[posname1]
        itime = np.mean([times[posname0], times[posname1]], axis=0)

        p = Pool()
        solutions = p.map(background_subtract_helper, xrange(len(bs.ssl)))
        p.close()

        write_outputs(solutions, itime, header, maskname, band, plan[i], options, target=target)
Ejemplo n.º 21
0
def handle_rectification(maskname, in_files, wavename, band_pass, files, options,
        commissioning_shift=3.0, target='default'):
    '''Handle slit rectification and coaddition.

    Args:
        maskname: The mask name string
        in_files: List of stacked spectra in electron per second. Will look
            like ['electrons_Offset_1.5.txt.fits', 'electrons_Offset_-1.5.txt.fits']
        wavename: path (relative or full) to the wavelength stack file, string
        band_pass: Band pass name, string
        barset_file: Path to a mosfire fits file containing the full set of
            FITS extensions for the barset. It can be any file in the list
            of science files.
    Returns:
        None

    Writes files:
        [maskname]_[band]_[object name]_eps.fits --
            The rectified, background subtracted, stacked eps spectrum
        [maskname]_[band]_[object name]_sig.fits --
            Rectified, background subtracted, stacked weight spectrum (STD/itime)
        [maskname]_[band]_[object_name]_itime.fits
            Rectified, CRR stacked integration time spectrum
        [maskname]_[band]_[object_name]_snrs.fits
            Rectified signal to noise spectrum
    '''

    global edges, dats, vars, itimes, shifts, lambdas, band, fidl, all_shifts
    band = band_pass

    
    dlambda = Wavelength.grating_results(band)

    hpp = Filters.hpp[band]
    fidl = np.arange(hpp[0], hpp[1], dlambda)

    lambdas = IO.readfits(wavename, options)

    if np.any(lambdas[1].data < 0) or np.any(lambdas[1].data > 29000):
        info("***********WARNING ***********")
        info("The file {0} may not be a wavelength file.".format(wavename))
        info("Check before proceeding.")
        info("***********WARNING ***********")

    edges, meta = IO.load_edges(maskname, band, options)
    shifts = []

    posnames = []
    postoshift = {}
    
    for file in in_files:

        info(":: "+str(file))
        II = IO.read_drpfits(maskname, file, options)

        off = np.array((II[0]["decoff"], II[0]["raoff"]),dtype=np.float64)
        if "yoffset" in II[0]:
            off = -II[0]["yoffset"]
        else:
            # Deal with data taken during commissioning
            if II[0]["frameid"] == 'A': off = 0.0
            else: off = commissioning_shift

        try: off0
        except: off0 = off

        shift = off - off0

        shifts.append(shift)
        posnames.append(II[0]["frameid"])
        postoshift[II[0]['frameid']] = shift
    
        info("Position {0} shift: {1:2.2f} as".format(off, shift))
    # this is to deal with cases in which we want to rectify one single file
    if len(set(posnames)) is 1:
        plans = [['A']]
    else:
        plans = Background.guess_plan_from_positions(set(posnames))

    all_shifts = []
    for plan in plans:
        to_append = []
        for pos in plan:
            to_append.append(postoshift[pos])

        all_shifts.append(to_append)

    # Reverse the elements in all_shifts to deal with an inversion
    all_shifts.reverse()

    theBPM = IO.badpixelmask()

    all_solutions = []
    cntr = 0

    if target is 'default':
        outname = maskname
    else:
        outname = target

    for plan in plans:
        if len(plan) is 1:
            p0 = 'A'
            p1 = 'B'
        else:
            p0 = plan[0].replace("'", "p")
            p1 = plan[1].replace("'", "p")
        suffix = "%s-%s" % (p0,p1)
        info("Handling plan %s" % suffix)
        fname = "bsub_{0}_{1}_{2}.fits".format(outname,band,suffix)
        EPS = IO.read_drpfits(maskname, fname, options)
        EPS[1] = np.ma.masked_array(EPS[1], theBPM, fill_value=0)

        fname = "var_{0}_{1}_{2}.fits".format(outname, band, suffix)
        VAR = IO.read_drpfits(maskname, fname, options)
        VAR[1] = np.ma.masked_array(VAR[1], theBPM, fill_value=np.inf)

        fname = "itime_{0}_{1}_{2}.fits".format(outname, band, suffix)
        ITIME = IO.read_drpfits(maskname, fname, options)
        ITIME[1] = np.ma.masked_array(ITIME[1], theBPM, fill_value=0)


        dats = EPS
        vars = VAR
        itimes = ITIME

        EPS[0]["ORIGFILE"] = fname

        tock = time.time()
        sols = range(len(edges)-1,-1,-1)

        shifts = all_shifts[cntr]
        cntr += 1
        p = Pool()
        solutions = p.map(handle_rectification_helper, sols)
        p.close()

        all_solutions.append(solutions)

    tick = time.time()
    info("-----> Mask took %i. Writing to disk." % (tick-tock))


    output = np.zeros((1, len(fidl)))
    snrs = np.zeros((1, len(fidl)))
    sdout= np.zeros((1, len(fidl)))
    itout= np.zeros((1, len(fidl)))


    # the barset [bs] is used for determining object position
    files = IO.list_file_to_strings(files)
    info("Using "+str(files[0])+" for slit configuration.")
    x, x, bs = IO.readmosfits(files[0], options)
    

    for i_slit in xrange(len(solutions)):
        solution = all_solutions[0][i_slit]
        header = EPS[0].copy()
        obj = header['OBJECT']

        target_name = bs.ssl[-(i_slit+1)]['Target_Name']
        header['OBJECT'] = target_name

        pixel_dist = np.float(bs.ssl[-(i_slit+1)]['Target_to_center_of_slit_distance'])/0.18

        pixel_dist -= solution['offset']

        ll = solution["lambda"]

        header["wat0_001"] = "system=world"
        header["wat1_001"] = "wtype=linear"
        header["wat2_001"] = "wtype=linear"
        header["dispaxis"] = 1
        header["dclog1"] = "Transform"
        header["dc-flag"] = 0
        header["ctype1"] = "AWAV"
        header["cunit1"] = "Angstrom"
        header["crval1"] = ll[0]
        header["crval2"] = -solution["eps_img"].shape[0]/2 - pixel_dist
        header["crpix1"] = 1
        header["crpix2"] = 1
        #remove redundant CDELTi due to wavelength issues with ds9
        #see: https://github.com/Keck-DataReductionPipelines/MosfireDRP/issues/44
        #header["cdelt1"] = 1
        #header["cdelt2"] = 1
        header["cname1"] = "angstrom"
        header["cname2"] = "pixel"
        header["cd1_1"] = ll[1]-ll[0]
        header["cd1_2"] = 0
        header["cd2_1"] = 0
        header["cd2_2"] = 1
        try:
            header["BARYCORR"]= (lambdas[0]['BARYCORR'],lambdas[0].comments['BARYCORR'])
        except KeyError:
            warning( "Barycentric corrections not applied to the wavelength solution")
            pass
        

        S = output.shape

        img = solution["eps_img"]
        std = solution["sd_img"]
        tms = solution["itime_img"]


        for i_solution in xrange(1,len(all_solutions)):
            info("Combining solution %i" %i_solution)
            solution = all_solutions[i_solution][i_slit]
            img += solution["eps_img"]
            std += solution["sd_img"]
            tms += solution["itime_img"]
        #print "adding in quadrature"
        
        output = np.append(output, img, 0)
        output = np.append(output, np.nan*np.zeros((3,S[1])), 0)
        snrs = np.append(snrs, img*tms/std, 0)
        snrs = np.append(snrs, np.nan*np.zeros((3,S[1])), 0)
        sdout = np.append(sdout, std, 0)
        sdout = np.append(sdout, np.nan*np.zeros((3,S[1])), 0)
        itout = np.append(itout, tms, 0)
        itout = np.append(itout, np.nan*np.zeros((3,S[1])), 0)

        header['bunit'] = ('electron/second', 'electron power')
        IO.writefits(img, maskname,
            "{0}_{1}_{2}_eps.fits".format(outname, band, target_name), options,
            overwrite=True, header=header, lossy_compress=False)

        header['bunit'] = ('electron/second', 'sigma/itime')
        IO.writefits(std/tms, maskname,
            "{0}_{1}_{2}_sig.fits".format(outname, band, target_name), options,
            overwrite=True, header=header, lossy_compress=False)

        header['bunit'] = ('second', 'exposure time')
        IO.writefits(tms, maskname,
            "{0}_{1}_{2}_itime.fits".format(outname, band, target_name), options,
            overwrite=True, header=header, lossy_compress=False)

        header['bunit'] = ('', 'SNR')
        IO.writefits(img*tms/std, maskname,
            "{0}_{1}_{2}_snrs.fits".format(outname, band, target_name), options,
            overwrite=True, header=header, lossy_compress=False)

    header = EPS[0].copy()
    header["wat0_001"] = "system=world"
    header["wat1_001"] = "wtype=linear"
    header["wat2_001"] = "wtype=linear"
    header["dispaxis"] = 1
    header["dclog1"] = "Transform"
    header["dc-flag"] = 0
    header["ctype1"] = "AWAV"
    header["cunit1"] = ("Angstrom", 'Start wavelength')
    header["crval1"] = ll[0]
    header["crval2"] = 1
    header["crpix1"] = 1
    header["crpix2"] = 1
    #remove redundant CDELTi due to wavelength issues with ds9
    #see: https://github.com/Keck-DataReductionPipelines/MosfireDRP/issues/44
    #header["cdelt1"] = 1
    #header["cdelt2"] = 1
    header["cname1"] = "angstrom"
    header["cname2"] = "pixel"
    header["cd1_1"] = (ll[1]-ll[0], 'Angstrom/pixel')
    header["cd1_2"] = 0
    header["cd2_1"] = 0
    header["cd2_2"] = 1
    try:
        header["BARYCORR"]= (lambdas[0]['BARYCORR'],lambdas[0].comments['BARYCORR'])
    except KeyError:
        warning( "Barycentric corrections not applied to the wavelength solution")
        pass


    header["bunit"] = "ELECTRONS/SECOND"
    info("############ Final reduced file: {0}_{1}_eps.fits".format(outname,band))
    IO.writefits(output, maskname, "{0}_{1}_eps.fits".format(outname,
        band), options, overwrite=True, header=header,
        lossy_compress=False)

    header["bunit"] = ""
    IO.writefits(snrs, maskname, "{0}_{1}_snrs.fits".format(outname,
        band), options, overwrite=True, header=header,
        lossy_compress=False)

    header["bunit"] = "ELECTRONS/SECOND"
    IO.writefits(sdout/itout, maskname, "{0}_{1}_sig.fits".format(outname,
        band), options, overwrite=True, header=header,
        lossy_compress=False)

    header["bunit"] = "SECOND"
    IO.writefits(itout, maskname, "{0}_{1}_itime.fits".format(outname,
        band), options, overwrite=True, header=header,
        lossy_compress=False)
Ejemplo n.º 22
0
def find_and_fit_edges(data, header, bs, options,edgeThreshold=450):
    '''
    Given a flat field image, find_and_fit_edges determines the position
    of all slits.

    The function works by starting with a guess at the location for a slit
    edge in the spatial direction(options["first-slit-edge"]). 
    
    Starting from the guess, find_edge_pair works out in either direction, 
    measuring the position of the (e.g.) bottom of slit 1 and top of slit 2:


    ------ pixel y value = 2048

    Slit 1 data

    ------ (bottom)
    deadband
    ------ (top)

    Slit N pixel data ....

    ------- (bottom) pixel = 0

    --------------------------------> Spectral direction


    1. At the top of the flat, the slit edge is defined to be a pixel value
    2. The code guesses the position of the bottom of the slit, and runs
            find_edge_pair to measure slit edge locations.
    3. A low-order polynomial is fit to the edge locations with
            fit_edge_poly
    4. The top and bottom of the current slit, is stored into the
            result list.
    5. The top of the next slit is stored temporarily for the next
            iteration of the for loop.
    6. At the bottom of the flat, the slit edge is defined to be pixel 4.


    options:
    options["edge-order"] -- The order of the polynomial [pixels] edge.
    options["edge-fit-width"] -- The length [pixels] of the edge to 
            fit over

    '''

    # TODO: move hardcoded values into Options.py
    # y is the location to start
    y = 2034
    DY = 44.25

    toc = 0
    ssl = bs.ssl

    slits = []

    top = [0., np.float(Options.npix)]

    start_slit_num = int(bs.msl[0]['Slit_Number'])-1
    if start_slit_num > 0:
        y -= DY * start_slit_num

    # Count and check that the # of objects in the SSL matches that of the MSL
    # This is purely a safety check
    numslits = np.zeros(len(ssl))
    for i in xrange(len(ssl)):
        slit = ssl[i]
        M = np.where(slit["Target_Name"] == bs.msl["Target_in_Slit"])

        numslits[i] = len(M[0])
    numslits = np.array(numslits)


    if (np.sum(numslits) != CSU.numslits) and (not bs.long_slit) and (not bs.long2pos_slit) and (not bs.long2pos_slit_specphot):
        error ("The number of allocated CSU slits (%i) does not match "
                " the number of possible slits (%i)." % (np.sum(numslits),
                    CSU.numslits))
        raise Exception("The number of allocated CSU slits (%i) does not match "
                " the number of possible slits (%i)." % (np.sum(numslits),
                    CSU.numslits))

    # if the mask is a long slit, the default y value will be wrong. Set instead to be the middle
    if bs.long_slit:
        y = 1104
        
    # now begin steps outline above
    results = []
    result = {}

    result["Target_Name"] = ssl[0]["Target_Name"]

    # 1
    result["top"] = np.poly1d([y])

    ''' Nomenclature here is confusing:
        
        ----- Edge  -- Top of current slit, bottom of prev slit
        . o ' Data
        ===== Data
        .;.;' Data
        ----- Edge  -- Bottom of current slit, top of next slit
    '''

    topfun = np.poly1d([y])
    xposs_top_this = np.arange(10,2000,100)
    yposs_top_this = topfun(xposs_top_this)

    for target in xrange(len(ssl)):

        y -= DY * numslits[target]
        y = max(y, 1)
        
        info("%2.2i] Finding Slit Edges for %s ending at %4.0i. Slit "
                "composed of %i CSU slits" % ( target,
                    ssl[target]["Target_Name"], y, numslits[target]))

        ''' First deal with the current slit '''
        hpps = Wavelength.estimate_half_power_points(
                bs.scislit_to_csuslit(target+1)[0], header, bs)

        if y == 1:
            xposs_bot = [1024]
            xposs_bot_missing = []
            yposs_bot = [4.25]
            botfun = np.poly1d(yposs_bot)
            ok = np.where((xposs_bot > hpps[0]) & (xposs_bot < hpps[1]))
        else:
            (xposs_top_next, xposs_top_next_missing, yposs_top_next, xposs_bot,
                xposs_bot_missing, yposs_bot, scatter_bot_this) = find_edge_pair(
                    data, y, options["edge-fit-width"],edgeThreshold=edgeThreshold)

            ok = np.where((xposs_bot > hpps[0]) & (xposs_bot < hpps[1]))
            ok2 = np.where((xposs_bot_missing > hpps[0]) & (xposs_bot_missing <
                hpps[1]))
            xposs_bot = xposs_bot[ok]
            xposs_bot_missing = xposs_bot_missing[ok2]
            yposs_bot = yposs_bot[ok]
            if len(xposs_bot) == 0:
                botfun = np.poly1d(y-DY)
            else:
                (botfun, bot_res, botsd, botok) =  fit_edge_poly(xposs_bot,
                         xposs_bot_missing, yposs_bot, options["edge-order"])


        bot = botfun.c.copy() 
        top = topfun.c.copy()

        #4
        result = {}
        result["Target_Name"] = ssl[target]["Target_Name"]
        result["xposs_top"] = xposs_top_this
        result["yposs_top"] = yposs_top_this
        result["xposs_bot"] = xposs_bot
        result["yposs_bot"] = yposs_bot
        result["top"] = np.poly1d(top)
        result["bottom"] = np.poly1d(bot)
        result["hpps"] = hpps
        result["ok"] = ok
        results.append(result)

        #5
        if y == 1:
            break
            

        next = target + 2
        if next > len(ssl): next = len(ssl)
        hpps_next = Wavelength.estimate_half_power_points(
                bs.scislit_to_csuslit(next)[0],
                    header, bs)

        ok = np.where((xposs_top_next > hpps_next[0]) & (xposs_top_next <
            hpps_next[1]))
        ok2 = np.where((xposs_top_next_missing > hpps_next[0]) &
            (xposs_top_next_missing < hpps_next[1]))

        xposs_top_next = xposs_top_next[ok]
        xposs_top_next_missing = xposs_top_next_missing[ok2]
        yposs_top_next = yposs_top_next[ok]

        if len(xposs_top_next) == 0:
            topfun = np.poly1d(y)
        else:
            (topfun, topres, topsd, ok) = fit_edge_poly(xposs_top_next,
                xposs_top_next_missing, yposs_top_next, options["edge-order"])

        xposs_top_this = xposs_top_next
        xposs_top_this_missing = xposs_top_next_missing
        yposs_top_this = yposs_top_next

    results.append({"version": options["version"]})

    return results
Ejemplo n.º 23
0
def imcombine(files, maskname, options, flat, outname=None, shifts=None,
    extension=None):
    '''
    From a list of files it imcombine returns the imcombine of several values.
    The imcombine code also estimates the readnoise ad RN/sqrt(numreads) so
    that the variance per frame is equal to (ADU + RN^2) where RN is computed
    in ADUs.

    Arguments:
        files[]: list of full path to files to combine
        maskname: Name of mask
        options: Options dictionary
        flat[2048x2048]: Flat field (values should all be ~ 1.0)
        outname: If set, will write (see notes below for details)
            eps_[outname].fits: electron/sec file
            itimes_[outname].fits: integration time
            var_[outname].fits: Variance files
        shifts[len(files)]: If set, will "roll" each file by the 
            amount in the shifts vector in pixels. This argument
            is used when telescope tracking is poor. If you need
            to use this, please notify Keck staff about poor 
            telescope tracking.

    Returns 6-element tuple:
        header: The combined header
        electrons [2048x2048]:  e- (in e- units)
        var [2048x2048]: electrons + RN**2 (in e-^2 units)
        bs: The MOSFIRE.Barset instance
        itimes [2048x2048]: itimes (in s units)
        Nframe: The number of frames that contribute to the summed
            arrays above. If Nframe > 5 I use the sigma-clipping
            Cosmic Ray Rejection tool. If Nframe < 5 then I drop
            the max/min elements.

    Notes:

        header -- fits header
        ADUs -- The mean # of ADUs per frame
        var -- the Variance [in adu] per frame. 
        bs -- Barset
        itimes -- The _total_ integration time in second
        Nframe -- The number of frames in a stack.

        
        Thus the number of electron per second is derived as: 
            e-/sec = (ADUs * Gain / Flat) * (Nframe/itimes)

        The total number of electrons is:
            el = ADUs * Gain * Nframe


    '''

    ADUs = np.zeros((len(files), 2048, 2048))
    itimes = np.zeros((len(files), 2048, 2048))
    prevssl = None
    prevmn = None
    patternid = None
    maskname = None

    header = None

    if shifts is None:
        shifts = np.zeros(len(files))

    warnings.filterwarnings('ignore')
    for i in xrange(len(files)):
        fname = files[i]
        thishdr, data, bs = IO.readmosfits(fname, options, extension=extension)
        itimes[i,:,:] = thishdr["truitime"]

        base = os.path.basename(fname).rstrip(".fits")
        fnum = int(base.split("_")[1])
        
        if shifts[i] == 0:
            ADUs[i,:,:] = data.filled(0.0) / flat
        else:
            ADUs[i,:,:] = np.roll(data.filled(0.0) / flat, np.int(shifts[i]), axis=0)

        ''' Construct Header'''
        if header is None:
            header = thishdr

        header["imfno%3.3i" % (fnum)] =  (fname, "img%3.3i file name" % fnum)

        map(lambda x: rem_header_key(header, x), ["CTYPE1", "CTYPE2", "WCSDIM",
            "CD1_1", "CD1_2", "CD2_1", "CD2_2", "LTM1_1", "LTM2_2", "WAT0_001",
            "WAT1_001", "WAT2_001", "CRVAL1", "CRVAL2", "CRPIX1", "CRPIX2",
            "RADECSYS"])

        for card in header.cards:
            if card == '': continue
            key,val,comment = card
            
            if key in thishdr:
                if val != thishdr[key]:
                    newkey = key + ("_img%2.2i" % fnum)
                    try: header[newkey.rstrip()] = (thishdr[key], comment)
                    except: pass

        ''' Now handle error checking'''

        if maskname is not None:
            if thishdr["maskname"] != maskname:
                error("File %s uses mask '%s' but the stack is of '%s'" %
                    (fname, thishdr["maskname"], maskname))
                raise Exception("File %s uses mask '%s' but the stack is of '%s'" %
                    (fname, thishdr["maskname"], maskname))

        maskname = thishdr["maskname"]
            
        if thishdr["aborted"]:
            error("Img '%s' was aborted and should not be used" %
                    fname)
            raise Exception("Img '%s' was aborted and should not be used" %
                    fname)

        if prevssl is not None:
            if len(prevssl) != len(bs.ssl):
                # todo Improve these checks
                error("The stack of input files seems to be of "
                        "different masks")
                raise Exception("The stack of input files seems to be of "
                        "different masks")
        prevssl = bs.ssl

        if patternid is not None:
            if patternid != thishdr["frameid"]:
                error("The stack should be of '%s' frames only, but "
                        "the current image is a '%s' frame." % (patternid, 
                            thishdr["frameid"]))
                raise Exception("The stack should be of '%s' frames only, but "
                        "the current image is a '%s' frame." % (patternid, 
                            thishdr["frameid"]))

        patternid = thishdr["frameid"]


        if maskname is not None:
            if maskname != thishdr["maskname"]:
                error("The stack should be of CSU mask '%s' frames "
                        "only but contains a frame of '%s'." % (maskname,
                        thishdr["maskname"]))
                raise Exception("The stack should be of CSU mask '%s' frames "
                        "only but contains a frame of '%s'." % (maskname,
                        thishdr["maskname"]))

        maskname = thishdr["maskname"]

        if thishdr["BUNIT"] != "ADU per coadd":
            error("The units of '%s' are not in ADU per coadd and "
                    "this violates an assumption of the DRP. Some new code " 
                    "is needed in the DRP to handle the new units of "
                    "'%s'." % (fname, thishdr["BUNIT"]))
            raise Exception("The units of '%s' are not in ADU per coadd and "
                    "this violates an assumption of the DRP. Some new code " 
                    "is needed in the DRP to handle the new units of "
                    "'%s'." % (fname, thishdr["BUNIT"]))

        ''' Error checking is complete'''
        debug("%s %s[%s]/%s: %5.1f s,  Shift: %i px" % (fname, maskname, patternid,
            header['filter'], np.mean(itimes[i]), shifts[i]))

    warnings.filterwarnings('always')

    # the electrons and el_per_sec arrays are:
    #   [2048, 2048, len(files)] and contain values for
    # each individual frame that is being combined.
    # These need to be kept here for CRR reasons.
    electrons = np.array(ADUs) * Detector.gain 
    el_per_sec = electrons / itimes

    output = np.zeros((2048, 2048))
    exptime = np.zeros((2048, 2048))

    numreads = header["READS0"]
    RN_adu = Detector.RN / np.sqrt(numreads) / Detector.gain
    RN = Detector.RN / np.sqrt(numreads)

    # Cosmic ray rejection code begins here. This code construction the
    # electrons and itimes arrays.
    standard = True
    new_from_chuck = False
    # Chuck Steidel has provided a modified version of the CRR procedure. 
    # to enable it, modify the variables above.
    
    if new_from_chuck and not standard:
        if len(files) >= 5:
            print "Sigclip CRR"
            srt = np.argsort(electrons, axis=0, kind='quicksort')
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            el_per_sec = el_per_sec[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            # Construct the mean and standard deviation by dropping the top and bottom two 
            # electron fluxes. This is temporary.
            mean = np.mean(el_per_sec[1:-1,:,:], axis = 0)
            std = np.std(el_per_sec[1:-1,:,:], axis = 0)

            drop = np.where( (el_per_sec > (mean+std*4)) | (el_per_sec < (mean-std*4)) )
            print "dropping: ", len(drop[0])
            electrons[drop] = 0.0
            itimes[drop] = 0.0

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 

        else:
            warning( "With less than 5 frames, the pipeline does NOT perform")
            warning( "Cosmic Ray Rejection.")
            # the "if false" line disables cosmic ray rejection"
            if False: 
                for i in xrange(len(files)):
                    el = electrons[i,:,:]
                    it = itimes[i,:,:]
                    el_mf = scipy.signal.medfilt(el, 5)

                    bad = np.abs(el - el_mf) / np.abs(el) > 10.0
                    el[bad] = 0.0
                    it[bad] = 0.0

                    electrons[i,:,:] = el
                    itimes[i,:,:] = it

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 

    if standard and not new_from_chuck:
        if len(files) >= 9:
            info("Sigclip CRR")
            srt = np.argsort(electrons, axis=0, kind='quicksort')
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            el_per_sec = el_per_sec[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            # Construct the mean and standard deviation by dropping the top and bottom two 
            # electron fluxes. This is temporary.
            mean = np.mean(el_per_sec[2:-2,:,:], axis = 0)
            std = np.std(el_per_sec[2:-2,:,:], axis = 0)

            drop = np.where( (el_per_sec > (mean+std*4)) | (el_per_sec < (mean-std*4)) )
            info("dropping: "+str(len(drop[0])))
            electrons[drop] = 0.0
            itimes[drop] = 0.0

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 

        elif len(files) > 5:
            warning( "WARNING: Drop min/max CRR")
            srt = np.argsort(el_per_sec,axis=0)
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            electrons = np.sum(electrons[1:-1,:,:], axis=0)
            itimes = np.sum(itimes[1:-1,:,:], axis=0)

            Nframe = len(files) - 2

        else:
            warning( "With less than 5 frames, the pipeline does NOT perform")
            warning( "Cosmic Ray Rejection.")
            # the "if false" line disables cosmic ray rejection"
            if False: 
                for i in xrange(len(files)):
                     el = electrons[i,:,:]
                     it = itimes[i,:,:]
                     # calculate the median image
                     el_mf = scipy.signal.medfilt(el, 5)
                     el_mf_large = scipy.signal.medfilt(el_mf, 15)
                     # LR: this is a modified version I was experimenting with. For the version 
                     #     written by Nick, see the new_from_chuck part of this code
                     # sky sub
                     el_sky_sub = el_mf - el_mf_large
                     # add a constant value
                     el_plus_constant = el_sky_sub + 100

                     bad = np.abs(el - el_mf) / np.abs(el_plus_constant) > 50.0
                     el[bad] = 0.0
                     it[bad] = 0.0

                     electrons[i,:,:] = el
                     itimes[i,:,:] = it

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 


    ''' Now handle variance '''
    numreads = header["READS0"]
    RN_adu = Detector.RN / np.sqrt(numreads) / Detector.gain
    RN = Detector.RN / np.sqrt(numreads)

    var = (electrons + RN**2) 

    ''' Now mask out bad pixels '''
    electrons[data.mask] = np.nan
    var[data.mask] = np.inf

    if "RN" in header:
        error("RN Already populated in header")
        raise Exception("RN Already populated in header")
    header['RN'] = ("%1.3f" , "Read noise in e-")
    header['NUMFRM'] = (Nframe, 'Typical number of frames in stack')


    header['BUNIT'] = 'ELECTRONS/SECOND'
    IO.writefits(np.float32(electrons/itimes), maskname, "eps_%s" % (outname),
                 options, header=header, overwrite=True)

    # Update itimes after division in order to not introduce nans
    itimes[data.mask] = 0.0

    header['BUNIT'] = 'ELECTRONS^2'
    IO.writefits(var, maskname, "var_%s" % (outname),
                 options, header=header, overwrite=True, lossy_compress=True)

    header['BUNIT'] = 'SECOND'
    IO.writefits(np.float32(itimes), maskname, "itimes_%s" % (outname),
                options, header=header, overwrite=True, lossy_compress=True)

    return header, electrons, var, bs, itimes, Nframe
Ejemplo n.º 24
0
def background_subtract_helper(slitno):
    '''

    Background subtraction follows the methods outlined by Kelson (2003). Here
    a background is estimated as a function of wavelength using B-splines and
    subtracted off. The assumption is that background is primarily a function
    of wavelength, and thus by sampling the background across the full 2-d
    spectrum the background is sampled at much higher than the native spectral
    resolution of mosfire. 

    Formally, the assumption that background is only a function of wavelength
    is incorrect, and indeed a "transmission function" is estimated from the 2d
    spectrum. This gives an estimate of the throughput of the slit and divided
    out.

    1. Extract the slit from the 2d image.
    2. Convert the 2d spectrum into a 1d spectrum
    3. Estimate transmission function

    '''

    global header, bs, edges, data, Var, itime, lam, sky_sub_out, sky_model_out, band
    tick = time.time()

    # 1
    top = np.int(edges[slitno]["top"](1024))  
    bottom = np.int(edges[slitno]["bottom"](1024)) 
    info("Background subtracting slit %i [%i,%i]" % (slitno, top, bottom))

    pix = np.arange(2048)
    xroi = slice(0,2048)
    yroi = slice(bottom, top)

    stime = itime[yroi, xroi]
    slit  = data[yroi, xroi] 
    Var[np.logical_not(np.isfinite(Var))] = np.inf

    lslit = lam[1][yroi,xroi]

    # 2
    xx = np.arange(slit.shape[1])
    yy = np.arange(slit.shape[0])

    X,Y = np.meshgrid(xx,yy)

    train_roi = slice(5,-5)
    ls = lslit[train_roi].flatten().filled(0)
    ss = slit[train_roi].flatten()
    ys = Y[train_roi].flatten()

    dl = np.ma.median(np.diff(lslit[lslit.shape[0]/2,:]))
    if dl == 0:
        return {"ok": False}

    sort = np.argsort(ls)
    ls = ls[sort]
    ys = ys[sort]

    hpps = np.array(Filters.hpp[band]) 

    diff = np.append(np.diff(ls), False)

    OK = (diff > 0.001) & (ls > hpps[0]) & (ls < hpps[1]) & (np.isfinite(ls)) \
            & (np.isfinite(ss[sort]))

    if len(np.where(OK)[0]) < 1000:
        warning("Failed on slit "+str(slitno))
        return {"ok": False}

    # 3
    pp = np.poly1d([1.0])
    ss = (slit[train_roi] / pp(Y[train_roi])).flatten()
    ss = ss[sort]

    knotstart = max(hpps[0], min(ls[OK])) + 5
    knotend = min(hpps[1], max(ls[OK])) - 5


    for i in range(3):
        try:
            delta = dl*0.9
            knots = np.arange(knotstart, knotend, delta)
            bspline = II.splrep(ls[OK], ss[OK], k=5, task=-1, t=knots)
        except ValueError as e:
            warning('Failed to fit spline with delta = {:5f}'.format(delta))
            warning(str(e))
            delta = dl*1.4
            info('Trying with delta = {:5f}'.format(delta))
            knots = np.arange(knotstart, knotend, delta)
            try:
                bspline = II.splrep(ls[OK], ss[OK], k=5, task=-1, t=knots)
            except ValueError as e:
                warning("Could not construct spline on slit "+str(slitno))
                warning(str(e))
                return {"ok": False}

        ll = lslit.flatten()
        model = II.splev(ll, bspline)

        oob = np.where((ll < knotstart) | (ll > knotend))
        model[oob] = np.median(ss[~np.isnan(ss)])
        model = model.reshape(slit.shape)

        output = slit - model

        std = np.abs(output)/(np.sqrt(np.abs(model)+1))

        tOK = (std[train_roi] < 10).flatten() & \
                np.isfinite(std[train_roi]).flatten()  
        OK = OK & tOK[sort]

    return {"ok": True, "slitno": slitno, "bottom": bottom, "top": top,
            "output": output, "model": model, "bspline": bspline}
Ejemplo n.º 25
0
def handle_rectification_helper(edgeno):
    ''' All the rectification happens in this helper function. This helper function
    is spawned as a separate process in the multiprocessing pool'''

    global edges, dats, vars, itimes, shifts, lambdas, band, fidl, all_shifts

    pix = np.arange(2048)
    kind = Options.wavelength["interpolation"]

    edge = edges[edgeno]

    info("Handling edge: " + str(edge["Target_Name"]))

    tops = edge["top"](pix)
    bots = edge["bottom"](pix)

    # Length of the slit in arcsecond
    lenas = (tops[1024] - bots[1024]) * 0.18
    mxshift = np.abs(np.int(np.ceil(np.max(all_shifts) / 0.18)))
    mnshift = np.abs(np.int(np.floor(np.min(all_shifts) / 0.18)))

    top = int(min(np.floor(np.min(tops)), 2048))
    bot = int(max(np.ceil(np.max(bots)), 0))

    ll = lambdas[1].data[bot:top, :]
    eps = dats[1][bot:top, :].filled(0.0)
    vv = vars[1][bot:top, :].filled(np.inf)
    it = itimes[1][bot:top, :].filled(0.0)

    lmid = ll[ll.shape[0] / 2, :]
    hpp = Filters.hpp[band]

    minl = lmid[0] if lmid[0] > hpp[0] else hpp[0]
    maxl = lmid[-1] if lmid[-1] < hpp[1] else hpp[1]

    epss = []
    ivss = []
    itss = []
    if len(shifts) is 1: sign = 1
    else: sign = -1
    for shift in shifts:
        output = r_interpol(ll,
                            eps,
                            fidl,
                            tops,
                            top,
                            shift_pix=shift / 0.18,
                            pad=[mnshift, mxshift],
                            fill_value=np.nan,
                            kind=kind)
        epss.append(sign * output)

        ivar = 1 / vv
        # Mask NaNs and infs from the variance array before interpolation
        # (only if not nearest neighbor)
        if kind is not "nearest":
            bad = np.where(np.isfinite(ivar) == 0)
            ivar[bad] = 0.0
        output = r_interpol(ll,
                            ivar,
                            fidl,
                            tops,
                            top,
                            shift_pix=shift / 0.18,
                            pad=[mnshift, mxshift],
                            fill_value=np.nan,
                            kind=kind)
        ivss.append(output)

        output = r_interpol(ll,
                            it,
                            fidl,
                            tops,
                            top,
                            shift_pix=shift / 0.18,
                            pad=[mnshift, mxshift],
                            fill_value=np.nan,
                            kind=kind)
        itss.append(output)

        sign *= -1
    # the "mean of empty slice" warning are generated at the top and bottom edges of the array
    # where there is basically no data due to the shifts between a and b positions
    # we could pad a little bit less, or accept the fact that the slits have a couple of rows of
    # nans in the results.
    warnings.filterwarnings('ignore', 'Mean of empty slice')
    it_img = np.nansum(np.array(itss), axis=0)
    eps_img = np.nanmean(epss, axis=0)
    warnings.filterwarnings('always')

    # Remove any NaNs or infs from the variance array
    ivar_img = []
    for ivar in ivss:
        bad = np.where(np.isfinite(ivar) == 0)
        ivar[bad] = 0.0

        ivar_img.append(ivar)

    IV = np.array(ivar_img)
    bad = np.isclose(IV, 0)
    IV[bad] = np.inf
    var_img = np.nanmean(1 / np.array(IV), axis=0)
    sd_img = np.sqrt(var_img)

    return {
        "eps_img": eps_img,
        "sd_img": sd_img,
        "itime_img": it_img,
        "lambda": fidl,
        "Target_Name": edge["Target_Name"],
        "slitno": edgeno + 1,
        "offset": np.max(tops - top)
    }
Ejemplo n.º 26
0
def find_longslit_edges(data,
                        header,
                        bs,
                        options,
                        edgeThreshold=450,
                        longslit=None):

    y = 2034
    DY = 44.25

    toc = 0
    ssl = bs.ssl

    slits = []

    top = [0., np.float(Options.npix)]

    start_slit_num = int(bs.msl[0]['Slit_Number']) - 1
    if start_slit_num > 0:
        y -= DY * start_slit_num
    # if the mask is a long slit, the default y value will be wrong. Set instead to be the middle
    if bs.long_slit:
        try:
            y = longslit["yrange"][1]
        except:
            error(
                "Longslit reduction mode is specified, but the row position has not been specified. Defaulting to "
                + str(y))
            print "Longslit reduction mode is specified, but the row position has not been specified. Defaulting to " + str(
                y)

    # Count and check that the # of objects in the SSL matches that of the MSL
    # This is purely a safety check
    numslits = np.zeros(len(ssl))
    for i in xrange(len(ssl)):
        slit = ssl[i]
        M = np.where(slit["Target_Name"] == bs.msl["Target_in_Slit"])

        numslits[i] = len(M[0])
    numslits = np.array(numslits)
    info("Number of slits allocated for this longslit: " +
         str(np.sum(numslits)))

    # now begin steps outline above
    results = []
    result = {}

    result["Target_Name"] = ssl[0]["Target_Name"]

    # 1 Defines a polynomial of degree 0, which is a constant, with the value of the top of the slit
    result["top"] = np.poly1d([longslit["yrange"][1]])

    topfun = np.poly1d([longslit["yrange"][1]
                        ])  # this is a constant funtion with c=top of the slit
    botfun = np.poly1d([
        longslit["yrange"][0]
    ])  # this is a constant funtion with c=bottom of the slit

    # xposs_top_this = [10 110 210 .... 1810 1910]
    xposs_top = np.arange(10, 2000, 100)
    xposs_bot = np.arange(10, 2000, 100)
    # yposs_top_this = [1104 1104 ... 1104 1104], it's the constant polynomium calculated at the X positions
    yposs_top = topfun(xposs_top)
    yposs_bot = botfun(xposs_bot)
    ''' Deal with the current slit '''
    target = 0
    hpps = Wavelength.estimate_half_power_points(
        bs.scislit_to_csuslit(target + 1)[0], header, bs)

    ok = np.where((xposs_top > hpps[0]) & (xposs_top < hpps[1]))

    xposs_bot = xposs_bot[ok]
    yposs_bot = yposs_bot[ok]
    xposs_top = xposs_top[ok]
    yposs_top = yposs_top[ok]

    if len(xposs_bot) == 0:
        error("The slit edges specifications appear to be incorrect.")
        raise Exception(
            "The slit edges specifications appear to be incorrect.")

    # bot is the polynomium that defines the shape of the bottom of the slit. In this case, we set it to a constant.
    bot = botfun.c.copy()
    top = topfun.c.copy()

    #4
    result = {}
    result["Target_Name"] = ssl[target]["Target_Name"]
    result["xposs_top"] = xposs_top
    result["yposs_top"] = yposs_top
    result["xposs_bot"] = xposs_bot
    result["yposs_bot"] = yposs_bot
    result["top"] = np.poly1d(top)
    result["bottom"] = np.poly1d(bot)
    result["hpps"] = hpps
    result["ok"] = ok
    results.append(result)

    results.append({"version": options["version"]})

    return results
Ejemplo n.º 27
0
def imcombine(files, maskname, options, flat, outname=None, shifts=None,
    extension=None):
    '''
    From a list of files it imcombine returns the imcombine of several values.
    The imcombine code also estimates the readnoise ad RN/sqrt(numreads) so
    that the variance per frame is equal to (ADU + RN^2) where RN is computed
    in ADUs.

    Arguments:
        files[]: list of full path to files to combine
        maskname: Name of mask
        options: Options dictionary
        flat[2048x2048]: Flat field (values should all be ~ 1.0)
        outname: If set, will write (see notes below for details)
            eps_[outname].fits: electron/sec file
            itimes_[outname].fits: integration time
            var_[outname].fits: Variance files
        shifts[len(files)]: If set, will "roll" each file by the 
            amount in the shifts vector in pixels. This argument
            is used when telescope tracking is poor. If you need
            to use this, please notify Keck staff about poor 
            telescope tracking.

    Returns 6-element tuple:
        header: The combined header
        electrons [2048x2048]:  e- (in e- units)
        var [2048x2048]: electrons + RN**2 (in e-^2 units)
        bs: The MOSFIRE.Barset instance
        itimes [2048x2048]: itimes (in s units)
        Nframe: The number of frames that contribute to the summed
            arrays above. If Nframe > 5 I use the sigma-clipping
            Cosmic Ray Rejection tool. If Nframe < 5 then I drop
            the max/min elements.

    Notes:

        header -- fits header
        ADUs -- The mean # of ADUs per frame
        var -- the Variance [in adu] per frame. 
        bs -- Barset
        itimes -- The _total_ integration time in second
        Nframe -- The number of frames in a stack.

        
        Thus the number of electron per second is derived as: 
            e-/sec = (ADUs * Gain / Flat) * (Nframe/itimes)

        The total number of electrons is:
            el = ADUs * Gain * Nframe


    '''

    ADUs = np.zeros((len(files), 2048, 2048))
    itimes = np.zeros((len(files), 2048, 2048))
    prevssl = None
    prevmn = None
    patternid = None
    maskname = None

    header = None

    if shifts is None:
        shifts = np.zeros(len(files))

    warnings.filterwarnings('ignore')
    for i in xrange(len(files)):
        fname = files[i]
        thishdr, data, bs = IO.readmosfits(fname, options, extension=extension)
        itimes[i,:,:] = thishdr["truitime"]

        base = os.path.basename(fname).rstrip(".fits")
        fnum = int(base.split("_")[1])
        
        if shifts[i] == 0:
            ADUs[i,:,:] = data.filled(0.0) / flat
        else:
            ADUs[i,:,:] = np.roll(data.filled(0.0) / flat, np.int(shifts[i]), axis=0)

        ''' Construct Header'''
        if header is None:
            header = thishdr

        header["imfno%3.3i" % (fnum)] =  (fname, "img%3.3i file name" % fnum)

        map(lambda x: rem_header_key(header, x), ["CTYPE1", "CTYPE2", "WCSDIM",
            "CD1_1", "CD1_2", "CD2_1", "CD2_2", "LTM1_1", "LTM2_2", "WAT0_001",
            "WAT1_001", "WAT2_001", "CRVAL1", "CRVAL2", "CRPIX1", "CRPIX2",
            "RADECSYS"])

        for card in header.cards:
            if card == '': continue
            key,val,comment = card
            
            if key in thishdr:
                if val != thishdr[key]:
                    newkey = key + ("_img%2.2i" % fnum)
                    try: header[newkey.rstrip()] = (thishdr[key], comment)
                    except: pass

        ''' Now handle error checking'''

        if maskname is not None:
            if thishdr["maskname"] != maskname:
                error("File %s uses mask '%s' but the stack is of '%s'" %
                    (fname, thishdr["maskname"], maskname))
                raise Exception("File %s uses mask '%s' but the stack is of '%s'" %
                    (fname, thishdr["maskname"], maskname))

        maskname = thishdr["maskname"]
            
        if thishdr["aborted"]:
            error("Img '%s' was aborted and should not be used" %
                    fname)
            raise Exception("Img '%s' was aborted and should not be used" %
                    fname)

        if prevssl is not None:
            if len(prevssl) != len(bs.ssl):
                # todo Improve these checks
                error("The stack of input files seems to be of "
                        "different masks")
                raise Exception("The stack of input files seems to be of "
                        "different masks")
        prevssl = bs.ssl

        if patternid is not None:
            if patternid != thishdr["frameid"]:
                error("The stack should be of '%s' frames only, but "
                        "the current image is a '%s' frame." % (patternid, 
                            thishdr["frameid"]))
                raise Exception("The stack should be of '%s' frames only, but "
                        "the current image is a '%s' frame." % (patternid, 
                            thishdr["frameid"]))

        patternid = thishdr["frameid"]


        if maskname is not None:
            if maskname != thishdr["maskname"]:
                error("The stack should be of CSU mask '%s' frames "
                        "only but contains a frame of '%s'." % (maskname,
                        thishdr["maskname"]))
                raise Exception("The stack should be of CSU mask '%s' frames "
                        "only but contains a frame of '%s'." % (maskname,
                        thishdr["maskname"]))

        maskname = thishdr["maskname"]

        if thishdr["BUNIT"] != "ADU per coadd":
            error("The units of '%s' are not in ADU per coadd and "
                    "this violates an assumption of the DRP. Some new code " 
                    "is needed in the DRP to handle the new units of "
                    "'%s'." % (fname, thishdr["BUNIT"]))
            raise Exception("The units of '%s' are not in ADU per coadd and "
                    "this violates an assumption of the DRP. Some new code " 
                    "is needed in the DRP to handle the new units of "
                    "'%s'." % (fname, thishdr["BUNIT"]))

        ''' Error checking is complete'''
        info("%s %s[%s]/%s: %5.1f s,  Shift: %i px" % (fname, maskname, patternid,
            header['filter'], np.mean(itimes[i]), shifts[i]))

    warnings.filterwarnings('always')

    # the electrons and el_per_sec arrays are:
    #   [2048, 2048, len(files)] and contain values for
    # each individual frame that is being combined.
    # These need to be kept here for CRR reasons.
    electrons = np.array(ADUs) * Detector.gain 
    el_per_sec = electrons / itimes

    output = np.zeros((2048, 2048))
    exptime = np.zeros((2048, 2048))

    numreads = header["READS0"]
    RN_adu = Detector.RN / np.sqrt(numreads) / Detector.gain
    RN = Detector.RN / np.sqrt(numreads)

    # Cosmic ray rejection code begins here. This code construction the
    # electrons and itimes arrays.
    standard = True
    new_from_chuck = False
    # Chuck Steidel has provided a modified version of the CRR procedure. 
    # to enable it, modify the variables above.
    
    if new_from_chuck and not standard:
        if len(files) >= 5:
            print "Sigclip CRR"
            srt = np.argsort(electrons, axis=0, kind='quicksort')
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            el_per_sec = el_per_sec[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            # Construct the mean and standard deviation by dropping the top and bottom two 
            # electron fluxes. This is temporary.
            mean = np.mean(el_per_sec[1:-1,:,:], axis = 0)
            std = np.std(el_per_sec[1:-1,:,:], axis = 0)

            drop = np.where( (el_per_sec > (mean+std*4)) | (el_per_sec < (mean-std*4)) )
            print "dropping: ", len(drop[0])
            electrons[drop] = 0.0
            itimes[drop] = 0.0

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 

        elif len(files) > 5:
            print "WARNING: Drop min/max CRR"
            srt = np.argsort(el_per_sec,axis=0)
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            electrons = np.sum(electrons[1:-1,:,:], axis=0)
            itimes = np.sum(itimes[1:-1,:,:], axis=0)

            Nframe = len(files) - 2

        else:
            warning( "With less than 5 frames, the pipeline does NOT perform")
            warning( "Cosmic Ray Rejection.")
            # the "if false" line disables cosmic ray rejection"
            if False: 
                for i in xrange(len(files)):
                    el = electrons[i,:,:]
                    it = itimes[i,:,:]
                    el_mf = scipy.signal.medfilt(el, 5)

                    bad = np.abs(el - el_mf) / np.abs(el) > 10.0
                    el[bad] = 0.0
                    it[bad] = 0.0

                    electrons[i,:,:] = el
                    itimes[i,:,:] = it

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 

    if standard and not new_from_chuck:
        if len(files) >= 9:
            info("Sigclip CRR")
            srt = np.argsort(electrons, axis=0, kind='quicksort')
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            el_per_sec = el_per_sec[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            # Construct the mean and standard deviation by dropping the top and bottom two 
            # electron fluxes. This is temporary.
            mean = np.mean(el_per_sec[2:-2,:,:], axis = 0)
            std = np.std(el_per_sec[2:-2,:,:], axis = 0)

            drop = np.where( (el_per_sec > (mean+std*4)) | (el_per_sec < (mean-std*4)) )
            info("dropping: "+str(len(drop[0])))
            electrons[drop] = 0.0
            itimes[drop] = 0.0

            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files) 
            


        elif len(files) > 5:
            warning( "WARNING: Drop min/max CRR")
            srt = np.argsort(el_per_sec,axis=0)
            shp = el_per_sec.shape
            sti = np.ogrid[0:shp[0], 0:shp[1], 0:shp[2]]

            electrons = electrons[srt, sti[1], sti[2]]
            itimes = itimes[srt, sti[1], sti[2]]

            electrons = np.sum(electrons[1:-1,:,:], axis=0)
            itimes = np.sum(itimes[1:-1,:,:], axis=0)

            Nframe = len(files) - 2

        else:
            warning( "With less than 5 frames, the pipeline does NOT perform")
            warning( "Cosmic Ray Rejection.")
            # the "if false" line disables cosmic ray rejection"
            if False: 
                for i in xrange(len(files)):
                     el = electrons[i,:,:]
                     it = itimes[i,:,:]
                     # calculate the median image
                     el_mf = scipy.signal.medfilt(el, 5)
                     el_mf_large = scipy.signal.medfilt(el_mf, 15)
                     # LR: this is a modified version I was experimenting with. For the version 
                     #     written by Nick, see the new_from_chuck part of this code
                     # sky sub
                     el_sky_sub = el_mf - el_mf_large
                     # add a constant value
                     el_plus_constant = el_sky_sub + 100

                     bad = np.abs(el - el_mf) / np.abs(el_plus_constant) > 50.0
                     el[bad] = 0.0
                     it[bad] = 0.0

                     electrons[i,:,:] = el
                     itimes[i,:,:] = it

            
            electrons = np.sum(electrons, axis=0)
            itimes = np.sum(itimes, axis=0)
            Nframe = len(files)


    ''' Now handle variance '''
    numreads = header["READS0"]
    RN_adu = Detector.RN / np.sqrt(numreads) / Detector.gain
    RN = Detector.RN / np.sqrt(numreads)

    var = (electrons + RN**2) 

    ''' Now mask out bad pixels '''
    electrons[data.mask] = np.nan
    var[data.mask] = np.inf
    
    print var[data.mask]

    if "RN" in header:
        error("RN Already populated in header")
        raise Exception("RN Already populated in header")
    header['RN'] = ("%1.3f" , "Read noise in e-")
    header['NUMFRM'] = (Nframe, 'Typical number of frames in stack')


    header['BUNIT'] = 'ELECTRONS/SECOND'
    IO.writefits(np.float32(electrons/itimes), maskname, "eps_%s" % (outname),
                 options, header=header, overwrite=True)

    # Update itimes after division in order to not introduce nans
    itimes[data.mask] = 0.0

    header['BUNIT'] = 'ELECTRONS^2'
    IO.writefits(var, maskname, "var_%s" % (outname),
                 options, header=header, overwrite=True, lossy_compress=True)

    header['BUNIT'] = 'SECOND'
    IO.writefits(np.float32(itimes), maskname, "itimes_%s" % (outname),
                options, header=header, overwrite=True, lossy_compress=True)

    return header, electrons, var, bs, itimes, Nframe
Ejemplo n.º 28
0
def handle_flats(flatlist, maskname, band, options, extension=None,edgeThreshold=450,lampOffList=None,longslit=None):
    '''
    handle_flats is the primary entry point to the Flats module.

    handle_flats takes a list of individual exposure FITS files and creates:
    1. A CRR, dark subtracted, pixel-response flat file.
    2. A set of polynomials that mark the edges of a slit

    Inputs:
    flatlist: 
    maskname: The name of a mask
    band: A string indicating the bandceil

    Outputs:

    file {maskname}/flat_2d_{band}.fits -- pixel response flat
    file {maskname}/edges.np
    '''

    tick = time.time()

    # Check
    bpos = np.ones(92) * -1

    #Retrieve the list of files to use for flat creation.
    flatlist = IO.list_file_to_strings(flatlist)
    # Print the filenames to Standard-out
    for flat in flatlist:
        info(str(flat))

    #Determine if flat files headers are in agreement
    for fname in flatlist:

        hdr, dat, bs = IO.readmosfits(fname, options, extension=extension)
        try: bs0
        except: bs0 = bs

        if np.any(bs0.pos != bs.pos):
            print "bs0: "+str(bs0.pos)+" bs: "+str(bs.pos)
            error("Barset do not seem to match")
            raise Exception("Barsets do not seem to match")

        if hdr["filter"] != band:
            error ("Filter name %s does not match header filter name "
                    "%s in file %s" % (band, hdr["filter"], fname))
            raise Exception("Filter name %s does not match header filter name "
                    "%s in file %s" % (band, hdr["filter"], fname))
        for i in xrange(len(bpos)):
            b = hdr["B{0:02d}POS".format(i+1)]
            if bpos[i] == -1:
                bpos[i] = b
            else:
                if bpos[i] != b:
                    error("Bar positions are not all the same in "
                            "this set of flat files")
                    raise Exception("Bar positions are not all the same in "
                            "this set of flat files")
    bs = bs0

    # Imcombine the lamps ON flats
    info("Attempting to combine previous files")
    combine(flatlist, maskname, band, options)

    # Imcombine the lamps OFF flats and subtract the off from the On sets
    if lampOffList != None: 
        #Retrieve the list of files to use for flat creation. 
        lampOffList = IO.list_file_to_strings(lampOffList)
        # Print the filenames to Standard-out
        for flat in lampOffList:
            info(str(flat))
        print "Attempting to combine Lamps off data"
        combine(lampOffList, maskname, band, options, lampsOff=True)
        combine_off_on( maskname, band, options)

    debug("Combined '%s' to '%s'" % (flatlist, maskname))
    info("Comgined to '%s'" % (maskname))
    path = "combflat_2d_%s.fits" % band
    (header, data) = IO.readfits(path, use_bpm=True)

    info("Flat written to %s" % path)

    # Edge Trace
    if bs.long_slit:
        info( "Long slit mode recognized")
        info( "Central row position:   "+str(longslit["row_position"]))
        info( "Upper and lower limits: "+str(longslit["yrange"][0])+" "+str(longslit["yrange"][1]))
        results = find_longslit_edges(data,header, bs, options, edgeThreshold=edgeThreshold, longslit=longslit)
    elif bs.long2pos_slit:
        info( "Long2pos mode recognized")
        results = find_long2pos_edges(data,header, bs, options, edgeThreshold=edgeThreshold, longslit=longslit)
    else:
        results = find_and_fit_edges(data, header, bs, options,edgeThreshold=edgeThreshold)
    results[-1]["maskname"] = maskname
    results[-1]["band"] = band
    np.save("slit-edges_{0}".format(band), results)
    save_ds9_edges(results, options)

    # Generate Flat
    out = "pixelflat_2d_%s.fits" % (band)
    if lampOffList != None: 
         make_pixel_flat(data, results, options, out, flatlist, lampsOff=True)
    else:
         make_pixel_flat(data, results, options, out, flatlist, lampsOff=False)

    info( "Pixel flat took {0:6.4} s".format(time.time()-tick))
Ejemplo n.º 29
0
def handle_rectification_helper(edgeno):
    ''' All the rectification happens in this helper function. This helper function
    is spawned as a separate process in the multiprocessing pool'''

    global edges, dats, vars, itimes, shifts, lambdas, band, fidl,all_shifts

    pix = np.arange(2048)
    
    edge = edges[edgeno]

    info("Handling edge: "+str(edge["Target_Name"]))

    tops = edge["top"](pix)
    bots = edge["bottom"](pix)

    # Length of the slit in arcsecond
    lenas = (tops[1024] - bots[1024]) * 0.18
    mxshift = np.abs(np.int(np.ceil(np.max(all_shifts)/0.18)))
    mnshift = np.abs(np.int(np.floor(np.min(all_shifts)/0.18)))
    
    top = int(min(np.floor(np.min(tops)), 2048))
    bot = int(max(np.ceil(np.max(bots)), 0))

    ll = lambdas[1].data[bot:top, :]
    eps = dats[1][bot:top, :].filled(0.0)
    vv = vars[1][bot:top, :].filled(np.inf)
    it  = itimes[1][bot:top, :].filled(0.0)

    lmid = ll[ll.shape[0]/2,:]
    hpp = Filters.hpp[band]

    minl = lmid[0] if lmid[0]>hpp[0] else hpp[0]
    maxl = lmid[-1] if lmid[-1]<hpp[1] else hpp[1]

    epss = []
    ivss = []
    itss = []
    if len(shifts) is 1: sign = 1
    else: sign = -1
    #Added by TN to print rectified non interpolated sig spectrum for Karl
    #hdu = pf.PrimaryHDU((vv)**0.5)
    #hdu.writeto('/Users/temp/mosdrp/output/COSMOS_Hmask4/2016jan7/H/'+str(edge["Target_Name"]) +'_offset_'+str(np.max(tops-top))+'.fits')
    
    
    for shift in shifts:
        output = r_interpol(ll, eps, fidl, tops, top, shift_pix=shift/0.18,
            pad=[mnshift, mxshift], fill_value = np.nan)
        epss.append(sign * output)

        ivar = 1/vv
        bad = np.where(np.isfinite(ivar) ==0)
        ivar[bad] = 0.0
        #TN: i've changed the code here (removed again)
        #to change back to DRP version remove 1/ in output
        #and ivss.append lines and remove **2
        output = r_interpol(ll,   ivar, fidl, tops, top, shift_pix=shift/0.18,
            pad=[mnshift, mxshift], fill_value=np.nan) 
        ivss.append(output)

        output = r_interpol(ll, it, fidl, tops, top, shift_pix=shift/0.18,
            pad=[mnshift, mxshift], fill_value=np.nan) 
        itss.append(output)

        sign *= -1

    it_img = np.nansum(np.array(itss), axis=0)
    eps_img = np.nanmean(epss, axis=0)

    # Remove any NaNs or infs from the variance array
    ivar_img = []
    for ivar in ivss:
        bad = np.where(np.isfinite(ivar) == 0)
        ivar[bad] = 0.0

        ivar_img.append(ivar)

    IV = np.array(ivar_img)
    bad = np.isclose(IV,0)
    IV[bad] = np.inf
    var_img = np.nanmean(1/np.array(IV), axis=0)
    sd_img = np.sqrt(var_img)
    
    
    return {"eps_img": eps_img, "sd_img": sd_img, "itime_img": it_img, 
            "lambda": fidl, "Target_Name": edge["Target_Name"], 
            "slitno": edgeno+1, "offset": np.max(tops-top)}
Ejemplo n.º 30
0
def find_longslit_edges(data, header, bs, options, edgeThreshold=450,longslit=None):


    y = 2034
    DY = 44.25


    toc = 0
    ssl = bs.ssl

    slits = []

    top = [0., np.float(Options.npix)]

    start_slit_num = int(bs.msl[0]['Slit_Number'])-1
    if start_slit_num > 0:
        y -= DY * start_slit_num
    # if the mask is a long slit, the default y value will be wrong. Set instead to be the middle
    if bs.long_slit:
        try:
            y=longslit["yrange"][1]
        except:
            error("Longslit reduction mode is specified, but the row position has not been specified. Defaulting to "+str(y))
            print "Longslit reduction mode is specified, but the row position has not been specified. Defaulting to "+str(y)


    # Count and check that the # of objects in the SSL matches that of the MSL
    # This is purely a safety check
    numslits = np.zeros(len(ssl))
    for i in xrange(len(ssl)):
        slit = ssl[i]
        M = np.where(slit["Target_Name"] == bs.msl["Target_in_Slit"])

        numslits[i] = len(M[0])
    numslits = np.array(numslits)
    info("Number of slits allocated for this longslit: "+str(np.sum(numslits)))

    # now begin steps outline above
    results = []
    result = {}

    result["Target_Name"] = ssl[0]["Target_Name"]

    # 1 Defines a polynomial of degree 0, which is a constant, with the value of the top of the slit
    result["top"] = np.poly1d([longslit["yrange"][1]])
    
    topfun = np.poly1d([longslit["yrange"][1]]) # this is a constant funtion with c=top of the slit
    botfun = np.poly1d([longslit["yrange"][0]]) # this is a constant funtion with c=bottom of the slit

    # xposs_top_this = [10 110 210 .... 1810 1910]
    xposs_top = np.arange(10,2000,100)
    xposs_bot = np.arange(10,2000,100)
    # yposs_top_this = [1104 1104 ... 1104 1104], it's the constant polynomium calculated at the X positions
    yposs_top = topfun(xposs_top)
    yposs_bot = botfun(xposs_bot)

    
    ''' Deal with the current slit '''
    target=0
    hpps = Wavelength.estimate_half_power_points(
                bs.scislit_to_csuslit(target+1)[0], header, bs)

    ok = np.where((xposs_top > hpps[0]) & (xposs_top < hpps[1]))

    xposs_bot = xposs_bot[ok]
    yposs_bot = yposs_bot[ok]
    xposs_top = xposs_top[ok]
    yposs_top = yposs_top[ok]

    if len(xposs_bot) == 0:
        error ("The slit edges specifications appear to be incorrect.")
        raise Exception("The slit edges specifications appear to be incorrect.")

    # bot is the polynomium that defines the shape of the bottom of the slit. In this case, we set it to a constant.
    bot = botfun.c.copy() 
    top = topfun.c.copy()


    #4
    result = {}
    result["Target_Name"] = ssl[target]["Target_Name"]
    result["xposs_top"] = xposs_top
    result["yposs_top"] = yposs_top
    result["xposs_bot"] = xposs_bot
    result["yposs_bot"] = yposs_bot
    result["top"] = np.poly1d(top)
    result["bottom"] = np.poly1d(bot)
    result["hpps"] = hpps
    result["ok"] = ok
    results.append(result)

    results.append({"version": options["version"]})

    return results
Ejemplo n.º 31
0
def writefits(img,
              maskname,
              fname,
              options,
              header=None,
              bs=None,
              overwrite=False,
              lossy_compress=False):
    '''Convenience wrapper to write MOSFIRE drp-friendly FITS files
    
    Args:
        img: Data array to write to disk
        maskname: Name of the science mask
        fname: Full or relative path to output file
        options: {} Unused
        header: Optional, the header to write
        bs: Optional unused
        overwrite: Force overwrite of file, default False/No.
        lossy_compress: Zero out the lowest order bits of the floats in
            order to make FITS files amenable to compression. The loss is
            at least 10 x less than 5e- which is the lowest reasonable read-
            noise value.

    Results:
        Writes a file to fname with data img and header header.

    '''

    if lossy_compress:
        hdu = pf.PrimaryHDU(floatcompress(img))
    else:
        hdu = pf.PrimaryHDU(img)

    fn = fname

    if header is None:
        header = {"DRPVER": (MOSFIRE.__version__, "DRP Version Date")}
    else:
        header["DRPVER"] = (MOSFIRE.__version__, 'DRP Version Date')

    warnings.filterwarnings('ignore')
    if header is not None:
        for k, value, comment in header.cards:
            if k in hdu.header: continue

            if k == 'COMMENT': continue
            if k == '': continue

            k = k.rstrip()
            hdu.header[k] = (value, comment)

    warnings.filterwarnings('always')
    if overwrite:
        try:
            os.remove(fn)
            debug("Removed old file '{0}'".format(fn))
        except:
            pass

    info("Wrote to '%s'" % (fn))
    warnings.filterwarnings('ignore',
                            'Card is too long, comment will be truncated.')
    hdu.writeto(fn)
    warnings.filterwarnings('always')
    if lossy_compress: os.system("gzip --force {0}".format(fn))
Ejemplo n.º 32
0
def make_pixel_flat(data, results, options, outfile, inputs, lampsOff=None):
    '''
    Convert a flat image into a flat field
    '''
    def pixel_min(y):
        return np.floor(np.min(y))

    def pixel_max(y):
        return np.ceil(np.max(y))

    def collapse_flat_box(dat):
        '''Collapse data to the spectral axis (0)'''
        v = np.median(dat, axis=0).ravel()

        return v

    flat = np.ones(shape=Detector.npix)

    hdu = pyfits.PrimaryHDU((data / flat).astype(np.float32))
    hdu.header.update("version", __version__, "DRP version")
    i = 0
    for flatname in inputs:
        nm = flatname.split("/")[-1]
        hdu.header.update("infile%2.2i" % i, nm)
        i += 1

    slitno = 0
    for result in results[0:-1]:
        slitno += 1

        hdu.header.update("targ%2.2i" % slitno, result["Target_Name"])

        bf = result["bottom"]
        tf = result["top"]
        try:
            hpps = result["hpps"]
        except:
            error("No half power points for this slit")
            hpps = [0, Detector.npix[0]]

        xs = np.arange(hpps[0], hpps[1])

        top = pixel_min(tf(xs))
        bottom = pixel_max(bf(xs))

        hdu.header.update("top%2.2i" % slitno, top)
        hdu.header.update("bottom%2.2i" % slitno, bottom)

        info("%s] Bounding top/bottom: %i/%i" %
             (result["Target_Name"], bottom, top))

        v = collapse_flat_box(data[bottom:top, hpps[0]:hpps[1]])

        x2048 = np.arange(Options.npix)
        v = np.poly1d(np.polyfit(xs, v,
                                 options['flat-field-order']))(xs).ravel()

        for i in np.arange(bottom - 1, top + 1):
            flat[i, hpps[0]:hpps[1]] = v

    info("Producing Pixel Flat...")
    for r in range(len(results) - 1):
        theslit = results[r]

        try:
            bf = theslit["bottom"]
            tf = theslit["top"]
        except:
            pdb.set_trace()

        for i in range(hpps[0], hpps[1]):
            top = np.floor(tf(i))
            bottom = np.ceil(bf(i))

            data[top:bottom, i] = flat[top:bottom, i]

    hdu.data = (data / flat).astype(np.float32)
    bad = np.abs(hdu.data - 1.0) > 0.5
    hdu.data[bad] = 1.0
    hdu.data = hdu.data.filled(1)
    if os.path.exists(outfile):
        os.remove(outfile)
    hdu.writeto(outfile)
Ejemplo n.º 33
0
    def set_header(self, header, ssl=None, msl=None, asl=None, targs=None):
        '''Passed "header" a FITS header dictionary and converts to a Barset'''
        self.pos = np.array(IO.parse_header_for_bars(header))
        self.set_pos_pix()

        self.ssl = ssl
        self.msl = msl
        self.asl = asl
        self.targs = targs

        def is_alignment_slit(slit):
            return (np.float(slit["Target_Priority"]) < 0)

        # If len(ssl) == 0 then the header is for a long slit
        if (header['MASKNAME'] == 'long2pos'):
            info("long2pos mode in CSU slit determination")
            self.long2pos_slit = True

        if (len(ssl) == 0):

            self.long_slit = True

            start = np.int(msl[0]["Slit_Number"])
            stop = np.int(msl[-1]["Slit_Number"])

            for mech_slit in msl:
                mech_slit["Target_in_Slit"] = "long"

            self.ssl = np.array([
                ("1", "??", "??", "??", "??", "??", "??", msl[0]['Slit_width'],
                 (stop - start + 1) * 7.6, "0", "long", "0")
            ],
                                dtype=[('Slit_Number', '|S2'),
                                       ('Slit_RA_Hours', '|S2'),
                                       ('Slit_RA_Minutes', '|S2'),
                                       ('Slit_RA_Seconds', '|S5'),
                                       ('Slit_Dec_Degrees', '|S3'),
                                       ('Slit_Dec_Minutes', '|S2'),
                                       ('Slit_Dec_Seconds', '|S5'),
                                       ('Slit_width', '|S5'),
                                       ('Slit_length', '|S5'),
                                       ('Target_to_center_of_slit_distance',
                                        '|S5'), ('Target_Name', '|S80'),
                                       ('Target_Priority', '|S1')])
            self.scislit_to_slit = [np.arange(start, stop)]
            ssl = None

        # Create a map between scislit number and mechanical slit
        # recall that slits count from 1
        if ssl is not None:
            prev = self.msl[0]["Target_in_Slit"]

            v = []

            for science_slit in ssl:
                targ = science_slit["Target_Name"]
                v.append([
                    int(x) for x in self.msl.field("Slit_Number")[np.where(
                        self.msl.field("Target_in_Slit").rstrip() == targ)[0]]
                ])
            self.scislit_to_slit = v

            if (len(self.scislit_to_slit) != len(ssl)
                ) and not (self.long_slit and len(self.scislit_to_slit) == 1):
                error("SSL should match targets in slit")
                raise Exception("SSL should match targets in slit")
Ejemplo n.º 34
0
def handle_flats(flatlist,
                 maskname,
                 band,
                 options,
                 extension=None,
                 edgeThreshold=450,
                 lampOffList=None,
                 longslit=None):
    '''
    handle_flats is the primary entry point to the Flats module.

    handle_flats takes a list of individual exposure FITS files and creates:
    1. A CRR, dark subtracted, pixel-response flat file.
    2. A set of polynomials that mark the edges of a slit

    Inputs:
    flatlist: 
    maskname: The name of a mask
    band: A string indicating the bandceil

    Outputs:

    file {maskname}/flat_2d_{band}.fits -- pixel response flat
    file {maskname}/edges.np
    '''

    tick = time.time()

    # Check
    bpos = np.ones(92) * -1

    #Retrieve the list of files to use for flat creation.
    flatlist = IO.list_file_to_strings(flatlist)
    # Print the filenames to Standard-out
    for flat in flatlist:
        info(str(flat))

    #Determine if flat files headers are in agreement
    for fname in flatlist:

        hdr, dat, bs = IO.readmosfits(fname, options, extension=extension)
        try:
            bs0
        except:
            bs0 = bs

        if np.any(bs0.pos != bs.pos):
            print "bs0: " + str(bs0.pos) + " bs: " + str(bs.pos)
            error("Barset do not seem to match")
            raise Exception("Barsets do not seem to match")

        if hdr["filter"] != band:
            error("Filter name %s does not match header filter name "
                  "%s in file %s" % (band, hdr["filter"], fname))
            raise Exception("Filter name %s does not match header filter name "
                            "%s in file %s" % (band, hdr["filter"], fname))
        for i in xrange(len(bpos)):
            b = hdr["B{0:02d}POS".format(i + 1)]
            if bpos[i] == -1:
                bpos[i] = b
            else:
                if bpos[i] != b:
                    error("Bar positions are not all the same in "
                          "this set of flat files")
                    raise Exception("Bar positions are not all the same in "
                                    "this set of flat files")
    bs = bs0

    # Imcombine the lamps ON flats
    info("Attempting to combine previous files")
    combine(flatlist, maskname, band, options)

    # Imcombine the lamps OFF flats and subtract the off from the On sets
    if lampOffList != None:
        #Retrieve the list of files to use for flat creation.
        lampOffList = IO.list_file_to_strings(lampOffList)
        # Print the filenames to Standard-out
        for flat in lampOffList:
            info(str(flat))
        print "Attempting to combine Lamps off data"
        combine(lampOffList, maskname, band, options, lampsOff=True)
        combine_off_on(maskname, band, options)

    debug("Combined '%s' to '%s'" % (flatlist, maskname))
    info("Comgined to '%s'" % (maskname))
    path = "combflat_2d_%s.fits" % band
    (header, data) = IO.readfits(path, use_bpm=True)

    info("Flat written to %s" % path)

    # Edge Trace
    if bs.long_slit:
        info("Long slit mode recognized")
        info("Central row position:   " + str(longslit["row_position"]))
        info("Upper and lower limits: " + str(longslit["yrange"][0]) + " " +
             str(longslit["yrange"][1]))
        results = find_longslit_edges(data,
                                      header,
                                      bs,
                                      options,
                                      edgeThreshold=edgeThreshold,
                                      longslit=longslit)
    elif bs.long2pos_slit:
        info("Long2pos mode recognized")
        results = find_long2pos_edges(data,
                                      header,
                                      bs,
                                      options,
                                      edgeThreshold=edgeThreshold,
                                      longslit=longslit)
    else:
        results = find_and_fit_edges(data,
                                     header,
                                     bs,
                                     options,
                                     edgeThreshold=edgeThreshold)
    results[-1]["maskname"] = maskname
    results[-1]["band"] = band
    np.save("slit-edges_{0}".format(band), results)
    save_ds9_edges(results, options)

    # Generate Flat
    out = "pixelflat_2d_%s.fits" % (band)
    if lampOffList != None:
        make_pixel_flat(data, results, options, out, flatlist, lampsOff=True)
    else:
        make_pixel_flat(data, results, options, out, flatlist, lampsOff=False)

    info("Pixel flat took {0:6.4} s".format(time.time() - tick))
Ejemplo n.º 35
0
def background_subtract_helper(slitno):
    '''

    Background subtraction follows the methods outlined by Kelson (2003). Here
    a background is estimated as a function of wavelength using B-splines and
    subtracted off. The assumption is that background is primarily a function
    of wavelength, and thus by sampling the background across the full 2-d
    spectrum the background is sampled at much higher than the native spectral
    resolution of mosfire. 

    Formally, the assumption that background is only a function of wavelength
    is incorrect, and indeed a "transmission function" is estimated from the 2d
    spectrum. This gives an estimate of the throughput of the slit and divided
    out.

    1. Extract the slit from the 2d image.
    2. Convert the 2d spectrum into a 1d spectrum
    3. Estimate transmission function

    '''

    global header, bs, edges, data, Var, itime, lam, sky_sub_out, sky_model_out, band
    tick = time.time()

    # 1
    top = np.int(edges[slitno]["top"](1024))  
    bottom = np.int(edges[slitno]["bottom"](1024)) 
    info("Background subtracting slit %i [%i,%i]" % (slitno, top, bottom))

    pix = np.arange(2048)
    xroi = slice(0,2048)
    yroi = slice(bottom, top)

    stime = itime[yroi, xroi]
    slit  = data[yroi, xroi] 
    Var[np.logical_not(np.isfinite(Var))] = np.inf

    lslit = lam[1][yroi,xroi]

    # 2
    xx = np.arange(slit.shape[1])
    yy = np.arange(slit.shape[0])

    X,Y = np.meshgrid(xx,yy)

    train_roi = slice(5,-5)
    ls = lslit[train_roi].flatten().filled(0)
    ss = slit[train_roi].flatten()
    ys = Y[train_roi].flatten()

    dl = np.ma.median(np.diff(lslit[lslit.shape[0]/2,:]))[0]
    if dl == 0:
        return {"ok": False}

    sort = np.argsort(ls)
    ls = ls[sort]
    ys = ys[sort]

    hpps = np.array(Filters.hpp[band]) 

    diff = np.append(np.diff(ls), False)

    OK = (diff > 0.001) & (ls > hpps[0]) & (ls < hpps[1]) & (np.isfinite(ls)) \
            & (np.isfinite(ss[sort]))

    if len(np.where(OK)[0]) < 1000:
        warning("Failed on slit "+str(slitno))
        return {"ok": False}

    # 3
    pp = np.poly1d([1.0])
    ss = (slit[train_roi] / pp(Y[train_roi])).flatten()
    ss = ss[sort]

    knotstart = max(hpps[0], min(ls[OK])) + 5
    knotend = min(hpps[1], max(ls[OK])) - 5


    for i in range(3):
        try:
            delta = dl*0.9
            knots = np.arange(knotstart, knotend, delta)
            bspline = II.splrep(ls[OK], ss[OK], k=5, task=-1, t=knots)
        except:
            delta = dl*1.4
            knots = np.arange(knotstart, knotend, delta)
            try:
                bspline = II.splrep(ls[OK], ss[OK], k=5, task=-1, t=knots)
            except:
                warning("Could not construct spline on slit "+str(slitno))
                return {"ok": False}

        ll = lslit.flatten()
        model = II.splev(ll, bspline)

        oob = np.where((ll < knotstart) | (ll > knotend))
        model[oob] = np.median(ss)
        model = model.reshape(slit.shape)

        output = slit - model

        std = np.abs(output)/(np.sqrt(np.abs(model)+1))

        tOK = (std[train_roi] < 10).flatten() & \
                np.isfinite(std[train_roi]).flatten()  
        OK = OK & tOK[sort]

    return {"ok": True, "slitno": slitno, "bottom": bottom, "top": top,
            "output": output, "model": model, "bspline": bspline}
Ejemplo n.º 36
0
def find_and_fit_edges(data, header, bs, options, edgeThreshold=450):
    '''
    Given a flat field image, find_and_fit_edges determines the position
    of all slits.

    The function works by starting with a guess at the location for a slit
    edge in the spatial direction(options["first-slit-edge"]). 
    
    Starting from the guess, find_edge_pair works out in either direction, 
    measuring the position of the (e.g.) bottom of slit 1 and top of slit 2:


    ------ pixel y value = 2048

    Slit 1 data

    ------ (bottom)
    deadband
    ------ (top)

    Slit N pixel data ....

    ------- (bottom) pixel = 0

    --------------------------------> Spectral direction


    1. At the top of the flat, the slit edge is defined to be a pixel value
    2. The code guesses the position of the bottom of the slit, and runs
            find_edge_pair to measure slit edge locations.
    3. A low-order polynomial is fit to the edge locations with
            fit_edge_poly
    4. The top and bottom of the current slit, is stored into the
            result list.
    5. The top of the next slit is stored temporarily for the next
            iteration of the for loop.
    6. At the bottom of the flat, the slit edge is defined to be pixel 4.


    options:
    options["edge-order"] -- The order of the polynomial [pixels] edge.
    options["edge-fit-width"] -- The length [pixels] of the edge to 
            fit over

    '''

    # TODO: move hardcoded values into Options.py
    # y is the location to start
    y = 2034
    DY = 44.25

    toc = 0
    ssl = bs.ssl

    slits = []

    top = [0., np.float(Options.npix)]

    start_slit_num = int(bs.msl[0]['Slit_Number']) - 1
    if start_slit_num > 0:
        y -= DY * start_slit_num

    # Count and check that the # of objects in the SSL matches that of the MSL
    # This is purely a safety check
    numslits = np.zeros(len(ssl))
    for i in xrange(len(ssl)):
        slit = ssl[i]
        M = np.where(slit["Target_Name"] == bs.msl["Target_in_Slit"])

        numslits[i] = len(M[0])
    numslits = np.array(numslits)

    if (np.sum(numslits) != CSU.numslits) and (not bs.long_slit) and (
            not bs.long2pos_slit) and (not bs.long2pos_slit_specphot):
        error("The number of allocated CSU slits (%i) does not match "
              " the number of possible slits (%i)." %
              (np.sum(numslits), CSU.numslits))
        raise Exception(
            "The number of allocated CSU slits (%i) does not match "
            " the number of possible slits (%i)." %
            (np.sum(numslits), CSU.numslits))

    # if the mask is a long slit, the default y value will be wrong. Set instead to be the middle
    if bs.long_slit:
        y = 1104

    # now begin steps outline above
    results = []
    result = {}

    result["Target_Name"] = ssl[0]["Target_Name"]

    # 1
    result["top"] = np.poly1d([y])
    ''' Nomenclature here is confusing:
        
        ----- Edge  -- Top of current slit, bottom of prev slit
        . o ' Data
        ===== Data
        .;.;' Data
        ----- Edge  -- Bottom of current slit, top of next slit
    '''

    topfun = np.poly1d([y])
    xposs_top_this = np.arange(10, 2000, 100)
    yposs_top_this = topfun(xposs_top_this)

    for target in xrange(len(ssl)):

        y -= DY * numslits[target]
        y = max(y, 1)

        info("%2.2i] Finding Slit Edges for %s ending at %4.0i. Slit "
             "composed of %i CSU slits" %
             (target, ssl[target]["Target_Name"], y, numslits[target]))
        ''' First deal with the current slit '''
        hpps = Wavelength.estimate_half_power_points(
            bs.scislit_to_csuslit(target + 1)[0], header, bs)

        if y == 1:
            xposs_bot = [1024]
            xposs_bot_missing = []
            yposs_bot = [4.25]
            botfun = np.poly1d(yposs_bot)
            ok = np.where((xposs_bot > hpps[0]) & (xposs_bot < hpps[1]))
        else:
            (xposs_top_next, xposs_top_next_missing, yposs_top_next, xposs_bot,
             xposs_bot_missing, yposs_bot,
             scatter_bot_this) = find_edge_pair(data,
                                                y,
                                                options["edge-fit-width"],
                                                edgeThreshold=edgeThreshold)

            ok = np.where((xposs_bot > hpps[0]) & (xposs_bot < hpps[1]))
            ok2 = np.where((xposs_bot_missing > hpps[0])
                           & (xposs_bot_missing < hpps[1]))
            xposs_bot = xposs_bot[ok]
            xposs_bot_missing = xposs_bot_missing[ok2]
            yposs_bot = yposs_bot[ok]
            if len(xposs_bot) == 0:
                botfun = np.poly1d(y - DY)
            else:
                (botfun, bot_res, botsd,
                 botok) = fit_edge_poly(xposs_bot, xposs_bot_missing,
                                        yposs_bot, options["edge-order"])

        bot = botfun.c.copy()
        top = topfun.c.copy()

        #4
        result = {}
        result["Target_Name"] = ssl[target]["Target_Name"]
        result["xposs_top"] = xposs_top_this
        result["yposs_top"] = yposs_top_this
        result["xposs_bot"] = xposs_bot
        result["yposs_bot"] = yposs_bot
        result["top"] = np.poly1d(top)
        result["bottom"] = np.poly1d(bot)
        result["hpps"] = hpps
        result["ok"] = ok
        results.append(result)

        #5
        if y == 1:
            break

        next = target + 2
        if next > len(ssl): next = len(ssl)
        hpps_next = Wavelength.estimate_half_power_points(
            bs.scislit_to_csuslit(next)[0], header, bs)

        ok = np.where((xposs_top_next > hpps_next[0])
                      & (xposs_top_next < hpps_next[1]))
        ok2 = np.where((xposs_top_next_missing > hpps_next[0])
                       & (xposs_top_next_missing < hpps_next[1]))

        xposs_top_next = xposs_top_next[ok]
        xposs_top_next_missing = xposs_top_next_missing[ok2]
        yposs_top_next = yposs_top_next[ok]

        if len(xposs_top_next) == 0:
            topfun = np.poly1d(y)
        else:
            (topfun, topres, topsd,
             ok) = fit_edge_poly(xposs_top_next, xposs_top_next_missing,
                                 yposs_top_next, options["edge-order"])

        xposs_top_this = xposs_top_next
        xposs_top_this_missing = xposs_top_next_missing
        yposs_top_this = yposs_top_next

    results.append({"version": options["version"]})

    return results
Ejemplo n.º 37
0
def handle_background(filelist, wavename, maskname, band_name, options,
                      shifts=None, plan=None, extension=None, target='default'): 
    '''
    Perform difference imaging and subtract residual background.

    The plan looks something like: [['A', 'B']]
    In this case, the number of output files is equal to the length of the list (1).

    If you choose to use an ABA'B' pattern then the plan will be: [["A", "B"], ["A'", "B'"]]
    the background subtraction code will make and handle two files, "A-B" and "A'-B'".
    '''
    
    global header, bs, edges, data, Var, itime, lam, sky_sub_out, sky_model_out, band

    band = band_name

    flatname = "pixelflat_2d_%s.fits" % band_name
    hdr, flat = IO.readfits("pixelflat_2d_%s.fits" % (band_name), options)

    if np.abs(np.median(flat) - 1) > 0.1:
        error("Flat seems poorly behaved.")
        raise Exception("Flat seems poorly behaved.")

    '''
        This next section of the code figures out the observing plan
        and then deals with the bookeeping of sending the plan
        to the background subtracter.
    '''

    hdrs = []
    epss = {}
    vars = {}
    bss = []
    times = {}
    Nframes = []

    i = 0
    header = pf.Header()
    for i in xrange(len(filelist)):
        fl = filelist[i]
        files = IO.list_file_to_strings(fl)
        info("Combining observation files listed in {}".format(fl))
        if shifts is None: shift = None
        else: shift = shifts[i]
        hdr, electron, var, bs, time, Nframe = imcombine(files, maskname,
            options, flat, outname="%s.fits" % (fl),
            shifts=shift, extension=extension)

        hdrs.append(hdr) 
        header = merge_headers(header, hdr)
        epss[hdr['FRAMEID']] = electron/time
        vars[hdr['FRAMEID']] = var
        times[hdr['FRAMEID']] = time
        bss.append(bs)
        Nframes.append(Nframe)

    positions = {}
    i = 0
    for h in hdrs:
        positions[h['FRAMEID']] = i
        i += 1
    posnames = set(positions.keys())
    if plan is None:
        plan = guess_plan_from_positions(posnames)

    num_outputs = len(plan)


    edges, meta = IO.load_edges(maskname, band, options)
    lam = IO.readfits(wavename, options)

    bs = bss[0]

    for i in xrange(num_outputs):
        posname0 = plan[i][0]
        posname1 = plan[i][1]
        info("Handling %s - %s" % (posname0, posname1))
        data = epss[posname0] - epss[posname1]
        Var = vars[posname0] + vars[posname1]
        itime = np.mean([times[posname0], times[posname1]], axis=0)

        p = Pool()
        solutions = p.map(background_subtract_helper, xrange(len(bs.ssl)))
        p.close()

        write_outputs(solutions, itime, header, maskname, band, plan[i], options, target=target)