Example #1
0
def center(xx):
    global imdata
    # The aperture size for finding the location of the stars is arbitrarily set here
    app = 7.
    flux = -photutils.aperture_circular(
        imdata, xx[0], xx[1], app, method='exact', subpixels=10)
    return flux
Example #2
0
    def _aperture_phot(self,
                       x,
                       y,
                       radsize=1,
                       sky_inner=5,
                       skywidth=5,
                       method="subpixel",
                       subpixels=4):
        """Perform sky subtracted aperture photometry, uses photutils functions, photutil must be installed

        Parameters
        ----------
        radsize: int
            Size of the radius

        sky_inner: int
            Inner radius of the sky annulus

        skywidth: int
            Width of the sky annulus

        method: string
            Pixel sampling method to use

        subpixels: int
            How many subpixels to use

        Notes
        -----
           background is taken from sky annulus pixels, check into masking bad pixels

        """
        if not photutils_installed:
            print("Install photutils to enable")
        else:

            aper_flux = photutils.aperture_circular(self._data,
                                                    x,
                                                    y,
                                                    radsize,
                                                    subpixels=subpixels,
                                                    method=method)
            aperture_area = np.pi * (radsize)**2

            annulus_sky = photutils.annulus_circular(self._data, x, y,
                                                     sky_inner,
                                                     sky_inner + skywidth)
            outer = sky_inner + skywidth
            inner = sky_inner
            annulus_area = np.pi * (outer**2 - inner**2)

            skysub_flux = aper_flux - annulus_sky * (aperture_area /
                                                     annulus_area)

            return (aper_flux, annulus_sky, skysub_flux)
Example #3
0
    def _aperture_phot(self,x,y,radsize=1,sky_inner=5,skywidth=5,method="subpixel",subpixels=4):
        """Perform sky subtracted aperture photometry, uses photutils functions
        
           background is taken from sky annulus pixels, check into masking
        """
        
        aper_flux=photutils.aperture_circular(self._data,x,y,radsize,subpixels=subpixels,method=method)
        aperture_area = np.pi * (radsize)**2

        annulus_sky=photutils.annulus_circular(self._data,x,y,sky_inner,sky_inner+skywidth)
        outer=sky_inner+skywidth
        inner=sky_inner
        annulus_area = np.pi * (outer**2 - inner**2)

        skysub_flux=aper_flux - annulus_sky  * (aperture_area / annulus_area)

        return (aper_flux,annulus_sky,skysub_flux)
Example #4
0
    def _aperture_phot(self, x, y, radsize=1, sky_inner=5, skywidth=5, method="subpixel", subpixels=4):
        """Perform sky subtracted aperture photometry, uses photutils functions, photutil must be installed

        Parameters
        ----------
        radsize: int
            Size of the radius

        sky_inner: int
            Inner radius of the sky annulus

        skywidth: int
            Width of the sky annulus

        method: string
            Pixel sampling method to use

        subpixels: int
            How many subpixels to use

        Notes
        -----
           background is taken from sky annulus pixels, check into masking bad pixels

        """
        if not photutils_installed:
            print("Install photutils to enable")
        else:

            aper_flux = photutils.aperture_circular(
                self._data, x, y, radsize, subpixels=subpixels, method=method)
            aperture_area = np.pi * (radsize) ** 2

            annulus_sky = photutils.annulus_circular(
                self._data, x, y, sky_inner, sky_inner + skywidth)
            outer = sky_inner + skywidth
            inner = sky_inner
            annulus_area = np.pi * (outer ** 2 - inner ** 2)

            skysub_flux = aper_flux - annulus_sky * (aperture_area / annulus_area)

            return (aper_flux, annulus_sky, skysub_flux)
Example #5
0
def get_fluxes(regfile, outfile, inneraprad=35, outeraprad=60, hdu=None,
        PPBEAM=1.0, debug=False, print_nulls=False, photut=True):
    """
    Extract fluxes from a region-defined aperture with inner and outer circular apertures
    specififed

    MUST BE IN GALACTIC COORDINATES
    """
    if hdu is None:
        raise ValueError("hdu keyword is required")

    data = hdu.data
    header = hdu.header
    wcs = pywcs.WCS(header)
    glonmax = wcs.wcs_pix2sky(0,0,0)[0]
    glonmin = wcs.wcs_pix2sky(data.shape[1],0,0)[1]

    reglist = pyregion.open(regfile)

    outf = open(outfile,'w')

    print "".join("%16s" % s for s in ['Source_Name','SumJy','ApSumJy','MeanApSumJy','SumJyBm','ApSumJyBm','BgMed','BgMean','BgStd','FracErrBg'])
    print >>outf,"".join("%16s" % s for s in ['Source_Name','SumJy','ApSumJy','MeanApSumJy','SumJyBm','ApSumJyBm','BgMed','BgMean','BgStd','FracErrBg'])

    if photut and not photut_ok:
        photut = False
        print "photutils is not loaded"
    if photut: 
        dsqueeze = data.squeeze()

    for reg in reglist:
        glon,glat = position_region(reg).galactic()
        if not((glon > glonmin) and (glon < glonmax)):
            # these are the limits of the survey
            if print_nulls:
                print >>outf,"%16s" % sourcename,"".join("%16s" % f 
                        for f in ['-','-','-','-','-','-','-','-','-'])
            continue
        xc,yc = wcs.wcs_sky2pix(glon,glat,0)
        if xc < 0 or xc > data.shape[1] or yc < 0 or yc > data.shape[0]:
            if print_nulls:
                print >>outf,"%16s" % sourcename,"".join("%16s" % f 
                        for f in ['-','-','-','-','-','-','-','-','-'])
            continue
        regL = pyregion.ShapeList()
        reg.name = 'circle'
        while len(reg.coord_list) < 3:
            reg.coord_list.append(0)
        reg.coord_list[2] = inneraprad/3600.0  # set inner aperture (foreground) to R=25"
        regL.append(reg)
        if not photut:
            innerap = regL.get_mask(hdu=hdu)
            if innerap.sum() == 0:
                print "Skipped a source that was in the boundaries: ",reg
                continue
        regL[0].coord_list[2] = outeraprad/3600.0  # set outer aperture (background) to R=100"
        #regL.append(reg) # I think this turns two circles into a panda?
        if not photut:
            outerap = regL.get_mask(hdu=hdu)
            backreg = outerap-innerap

        if photut:
            innerappix = inneraprad / 3600. / np.abs(wcs.wcs.get_cdelt()[0]) / 2.
            outerappix = outeraprad / 3600. / np.abs(wcs.wcs.get_cdelt()[0]) / 2.
            total = photutils.aperture_circular(dsqueeze, xc, yc, innerappix)
            outer = photutils.aperture_circular(dsqueeze, xc, yc, outerappix)
            background = (outer-total) / ((outerappix**2-innerappix**2)*np.pi)
            backmean = background
            backstd = np.nan
        else:
            total = data[innerap].sum()
            background = np.median(data[backreg])
            backmean = data[backreg].mean()
            backstd = data[backreg].std()

        sourcename = pos_to_name(reg)

        if backstd > total or total < 0:
            print "%s set to zero" % reg.attr[1]['text']
            total = np.float(0)
            total_backsub  = np.float(0)
            total_mbacksub = np.float(0)
        else:
            if photut:
                total_backsub = total_mbacksub = outer-total
            else:
                total_backsub  = total - innerap.sum() * background
                total_mbacksub = total - innerap.sum() * backmean

        if total_backsub == 0:
            total_backsub = -np.inf

        print "%16s" % sourcename,"".join("%16.5g" % f 
                for f in [total/PPBEAM,total_backsub/PPBEAM,total_mbacksub/PPBEAM,total,total_backsub,background,backmean,backstd,backstd/total_backsub])
        print >>outf,"%16s" % sourcename,"".join("%16.5g" % f 
                for f in [total/PPBEAM,total_backsub/PPBEAM,total_mbacksub/PPBEAM,total,total_backsub,background,backmean,backstd,backstd/total_backsub])

    print "Done with %s" % outfile
    outf.close()
Example #6
0
def aperture(image, hdr):
    global iap, pguess_old, nstars, svec
    dnorm = 500.
    rann1 = 18.
    dann = 2.
    rann2 = rann1 + dann
    app_min = 1.
    app_max = 19.
    dapp = 1.
    app_sizes = np.arange(app_min, app_max, dapp)

    # If first time through, read in "guesses" for locations of stars
    if iap == 0:
        var = np.loadtxt('phot_coords')
        xvec = var[:, 0]
        yvec = var[:, 1]
        nstars = len(xvec)
        #print app_sizes,'\n'
    else:
        xvec = svec[:, 0]
        yvec = svec[:, 1]

    # Find locations of stars
    dxx0 = 10.
    for i in range(nstars):
        xx0 = [xvec[i], yvec[i]]
        xbounds = (xx0[0] - dxx0, xx0[0] + dxx0)
        ybounds = (xx0[1] - dxx0, xx0[1] + dxx0)
        #res = sco.minimize(center, xx0, method='BFGS', jac=der_center)
        #res = sco.fmin_tnc(center, xx0, bounds=(xbounds,ybounds))
        #res = sco.minimize(center, xx0, method='tnc', bounds=(xbounds,ybounds))
        res = sco.minimize(center,
                           xx0,
                           method='L-BFGS-B',
                           bounds=(xbounds, ybounds),
                           jac=der_center)
        xx0 = res.x
        xvec[i] = xx0[0]
        yvec[i] = xx0[1]

    # Calculate sky around stars
    sky = photutils.annulus_circular(image,
                                     xvec,
                                     yvec,
                                     rann1,
                                     rann2,
                                     method='exact',
                                     subpixels=10)

    # Do psf fits to stars. Results are stored in arrays fwhm, pflux, psky, psf_x, and psf_y
    fwhm = np.zeros(nstars)

    # Make stacked array of star positions from aperture photometry
    svec = np.dstack((xvec, yvec))[0]
    #print svec

    # Make stacked array of star positions from PSF fitting
    # pvec = np.dstack((psf_x,psf_y))[0]
    pvec = svec

    iap = iap + 1

    starr = []
    apvec = []
    app = -1.0

    # Get time of observation from the header
    #date = hdr['DATE-OBS']   # for Argos files
    #utc  = hdr['UTC']         # for Argos files
    date = hdr['UTC-DATE']  # for Pro-EM files
    utc = hdr['UTC-BEG']  # for Pro-EM files
    times = date + "  " + utc
    t = Time(times, format='iso', scale='utc')
    # Calculate Julian Date of observation
    jd = t.jd
    for app in app_sizes:
        flux = photutils.aperture_circular(image,
                                           xvec,
                                           yvec,
                                           app,
                                           method='exact',
                                           subpixels=10)
        skyc = sky * app**2 / (rann2**2 - rann1**2)
        fluxc = flux - skyc
        starr.append([fluxc, skyc, fwhm])
        apvec.append(app)
    starr = np.array(starr)
    apvec = np.array(apvec)
    #print starr
    return jd, svec, pvec, apvec, starr
Example #7
0
def get_fluxes(regfile,
               outfile,
               inneraprad=35,
               outeraprad=60,
               hdu=None,
               PPBEAM=1.0,
               debug=False,
               print_nulls=False,
               photut=True):
    """
    Extract fluxes from a region-defined aperture with inner and outer circular apertures
    specififed

    MUST BE IN GALACTIC COORDINATES
    """
    if hdu is None:
        raise ValueError("hdu keyword is required")

    data = hdu.data
    header = hdu.header
    wcs = pywcs.WCS(header)
    glonmax = wcs.wcs_pix2sky(0, 0, 0)[0]
    glonmin = wcs.wcs_pix2sky(data.shape[1], 0, 0)[1]

    reglist = pyregion.open(regfile)

    outf = open(outfile, 'w')

    print "".join("%16s" % s for s in [
        'Source_Name', 'SumJy', 'ApSumJy', 'MeanApSumJy', 'SumJyBm',
        'ApSumJyBm', 'BgMed', 'BgMean', 'BgStd', 'FracErrBg'
    ])
    print >> outf, "".join("%16s" % s for s in [
        'Source_Name', 'SumJy', 'ApSumJy', 'MeanApSumJy', 'SumJyBm',
        'ApSumJyBm', 'BgMed', 'BgMean', 'BgStd', 'FracErrBg'
    ])

    if photut and not photut_ok:
        photut = False
        print "photutils is not loaded"
    if photut:
        dsqueeze = data.squeeze()

    for reg in reglist:
        glon, glat = position_region(reg).galactic()
        if not ((glon > glonmin) and (glon < glonmax)):
            # these are the limits of the survey
            if print_nulls:
                print >> outf, "%16s" % sourcename, "".join(
                    "%16s" % f
                    for f in ['-', '-', '-', '-', '-', '-', '-', '-', '-'])
            continue
        xc, yc = wcs.wcs_sky2pix(glon, glat, 0)
        if xc < 0 or xc > data.shape[1] or yc < 0 or yc > data.shape[0]:
            if print_nulls:
                print >> outf, "%16s" % sourcename, "".join(
                    "%16s" % f
                    for f in ['-', '-', '-', '-', '-', '-', '-', '-', '-'])
            continue
        regL = pyregion.ShapeList()
        reg.name = 'circle'
        while len(reg.coord_list) < 3:
            reg.coord_list.append(0)
        reg.coord_list[
            2] = inneraprad / 3600.0  # set inner aperture (foreground) to R=25"
        regL.append(reg)
        if not photut:
            innerap = regL.get_mask(hdu=hdu)
            if innerap.sum() == 0:
                print "Skipped a source that was in the boundaries: ", reg
                continue
        regL[0].coord_list[
            2] = outeraprad / 3600.0  # set outer aperture (background) to R=100"
        #regL.append(reg) # I think this turns two circles into a panda?
        if not photut:
            outerap = regL.get_mask(hdu=hdu)
            backreg = outerap - innerap

        if photut:
            innerappix = inneraprad / 3600. / np.abs(
                wcs.wcs.get_cdelt()[0]) / 2.
            outerappix = outeraprad / 3600. / np.abs(
                wcs.wcs.get_cdelt()[0]) / 2.
            total = photutils.aperture_circular(dsqueeze, xc, yc, innerappix)
            outer = photutils.aperture_circular(dsqueeze, xc, yc, outerappix)
            background = (outer - total) / (
                (outerappix**2 - innerappix**2) * np.pi)
            backmean = background
            backstd = np.nan
        else:
            total = data[innerap].sum()
            background = np.median(data[backreg])
            backmean = data[backreg].mean()
            backstd = data[backreg].std()

        sourcename = pos_to_name(reg)

        if backstd > total or total < 0:
            print "%s set to zero" % reg.attr[1]['text']
            total = np.float(0)
            total_backsub = np.float(0)
            total_mbacksub = np.float(0)
        else:
            if photut:
                total_backsub = total_mbacksub = outer - total
            else:
                total_backsub = total - innerap.sum() * background
                total_mbacksub = total - innerap.sum() * backmean

        if total_backsub == 0:
            total_backsub = -np.inf

        print "%16s" % sourcename, "".join("%16.5g" % f for f in [
            total / PPBEAM, total_backsub / PPBEAM, total_mbacksub / PPBEAM,
            total, total_backsub, background, backmean, backstd, backstd /
            total_backsub
        ])
        print >> outf, "%16s" % sourcename, "".join("%16.5g" % f for f in [
            total / PPBEAM, total_backsub / PPBEAM, total_mbacksub / PPBEAM,
            total, total_backsub, background, backmean, backstd, backstd /
            total_backsub
        ])

    print "Done with %s" % outfile
    outf.close()