Exemple #1
0
 def galaxy_norm(self, tim, x=None, y=None):
     # Galaxy-detection norm
     from tractor.galaxy import ExpGalaxy
     from tractor.ellipses import EllipseE
     from tractor.patch import ModelMask
     h, w = tim.shape
     band = tim.band
     if x is None:
         x = w / 2.
     if y is None:
         y = h / 2.
     pos = tim.wcs.pixelToPosition(x, y)
     gal = SimpleGalaxy(pos, NanoMaggies(**{band: 1.}))
     S = 32
     mm = ModelMask(int(x - S), int(y - S), 2 * S + 1, 2 * S + 1)
     galmod = gal.getModelPatch(tim, modelMask=mm).patch
     galmod = np.maximum(0, galmod)
     galmod /= galmod.sum()
     galnorm = np.sqrt(np.sum(galmod**2))
     return galnorm
def psf_residuals(expnum,
                  ccdname,
                  stampsize=35,
                  nstar=30,
                  magrange=(13, 17),
                  verbose=0,
                  splinesky=False):

    # Set the debugging level.
    if verbose == 0:
        lvl = logging.INFO
    else:
        lvl = logging.DEBUG
    logging.basicConfig(level=lvl, format='%(message)s', stream=sys.stdout)

    pngprefix = 'qapsf-{}-{}'.format(expnum, ccdname)

    # Gather all the info we need about this CCD.
    decals = Decals()
    ccd = decals.find_ccds(expnum=expnum, ccdname=ccdname)[0]
    band = ccd.filter
    ps1band = dict(g=0, r=1, i=2, z=3, Y=4)
    print('Band {}'.format(band))

    #scales = dict(g=0.0066, r=0.01, z=0.025)
    #vmin, vmax = np.arcsinh(-1), np.arcsinh(100)
    #print(scales[band])

    im = decals.get_image_object(ccd)
    iminfo = im.get_image_info()
    H, W = iminfo['dims']

    wcs = im.get_wcs()

    # Choose a uniformly selected subset of PS1 stars on this CCD.
    ps1 = ps1cat(ccdwcs=wcs)
    cat = ps1.get_stars(band=band, magrange=magrange)

    rand = np.random.RandomState(seed=expnum * ccd.ccdnum)
    these = rand.choice(len(cat) - 1, nstar, replace=False)
    #these = rand.random_integers(0,len(cat)-1,nstar)
    cat = cat[these]
    cat = cat[np.argsort(cat.median[:, ps1band[band]])]  # sort by magnitude
    #print(cat.nmag_ok)

    get_tim_kwargs = dict(const2psf=True, splinesky=splinesky)

    # Make a QAplot of the positions of all the stars.
    tim = im.get_tractor_image(**get_tim_kwargs)
    img = tim.getImage()
    #img = tim.getImage()/scales[band]

    fig = plt.figure(figsize=(5, 10))
    ax = fig.gca()
    ax.get_xaxis().get_major_formatter().set_useOffset(False)
    #ax.imshow(np.arcsinh(img),cmap='gray',interpolation='nearest',
    #          origin='lower',vmin=vmax,vmax=vmax)

    ax.imshow(img, **tim.ima)
    ax.axis('off')
    ax.set_title('{}: {}/{} AM={:.2f} Seeing={:.3f}"'.format(
        band, expnum, ccdname, ccd.airmass, ccd.seeing))

    for istar, ps1star in enumerate(cat):
        ra, dec = (ps1star.ra, ps1star.dec)
        ok, xpos, ypos = wcs.radec2pixelxy(ra, dec)
        ax.text(xpos,
                ypos,
                '{:2d}'.format(istar + 1),
                color='red',
                horizontalalignment='left')
        circ = plt.Circle((xpos, ypos), radius=30, color='g', fill=False, lw=1)
        ax.add_patch(circ)

    #radec = wcs.radec_bounds()
    #ax.scatter(cat.ra,cat.dec)
    #ax.set_xlim([radec[1],radec[0]])#*[1.0002,0.9998])
    #ax.set_ylim([radec[2],radec[3]])#*[0.985,1.015])
    #ax.set_xlabel('$RA\ (deg)$',fontsize=18)
    #ax.set_ylabel('$Dec\ (deg)$',fontsize=18)
    fig.savefig(pngprefix + '-ccd.png', bbox_inches='tight')

    # Initialize the many-stamp QAplot
    ncols = 3
    nrows = np.ceil(nstar / ncols).astype('int')

    inchperstamp = 2.0
    fig = plt.figure(figsize=(inchperstamp * 3 * ncols, inchperstamp * nrows))
    irow = 0
    icol = 0

    for istar, ps1star in enumerate(cat):
        ra, dec = (ps1star.ra, ps1star.dec)
        mag = ps1star.median[ps1band[band]]  # r-band

        ok, xpos, ypos = wcs.radec2pixelxy(ra, dec)
        ix, iy = int(xpos), int(ypos)

        # create a little tractor Image object around the star
        slc = (slice(max(iy - stampsize, 0), min(iy + stampsize + 1, H)),
               slice(max(ix - stampsize, 0), min(ix + stampsize + 1, W)))

        # The PSF model 'const2Psf' is the one used in DR1: a 2-component
        # Gaussian fit to PsfEx instantiated in the image center.
        tim = im.get_tractor_image(slc=slc, **get_tim_kwargs)
        stamp = tim.getImage()
        ivarstamp = tim.getInvvar()

        # Initialize a tractor PointSource from PS1 measurements
        flux = NanoMaggies.magToNanomaggies(mag)
        star = PointSource(RaDecPos(ra, dec), NanoMaggies(**{band: flux}))

        # Fit just the source RA,Dec,flux.
        tractor = Tractor([tim], [star])
        tractor.freezeParam('images')

        print('2-component MOG:', tim.psf)
        tractor.printThawedParams()

        for step in range(50):
            dlnp, X, alpha = tractor.optimize()
            if dlnp < 0.1:
                break
        print('Fit:', star)
        model_mog = tractor.getModelImage(0)
        chi2_mog = -2.0 * tractor.getLogLikelihood()
        mag_mog = NanoMaggies.nanomaggiesToMag(star.brightness)[0]

        # Now change the PSF model to a pixelized PSF model from PsfEx instantiated
        # at this place in the image.
        psf = PixelizedPsfEx(im.psffn)
        tim.psf = psf.constantPsfAt(xpos, ypos)

        #print('PSF model:', tim.psf)
        #tractor.printThawedParams()
        for step in range(50):
            dlnp, X, alpha = tractor.optimize()
            if dlnp < 0.1:
                break

        print('Fit:', star)
        model_psfex = tractor.getModelImage(0)
        chi2_psfex = -2.0 * tractor.getLogLikelihood()
        mag_psfex = NanoMaggies.nanomaggiesToMag(star.brightness)[0]

        #mn, mx = np.percentile((stamp-model_psfex)[ivarstamp>0],[1,95])
        sig = np.std((stamp - model_psfex)[ivarstamp > 0])
        mn, mx = [-2.0 * sig, 5 * sig]

        # Generate a QAplot.
        if (istar > 0) and (istar % (ncols) == 0):
            irow = irow + 1
        icol = 3 * istar - 3 * ncols * irow
        #print(istar, irow, icol, icol+1, icol+2)

        ax1 = plt.subplot2grid((nrows, 3 * ncols), (irow, icol),
                               aspect='equal')
        ax1.axis('off')
        #ax1.imshow(stamp, **tim.ima)
        ax1.imshow(stamp,
                   cmap='gray',
                   interpolation='nearest',
                   origin='lower',
                   vmin=mn,
                   vmax=mx)
        ax1.text(0.1,
                 0.9,
                 '{:2d}'.format(istar + 1),
                 color='white',
                 horizontalalignment='left',
                 verticalalignment='top',
                 transform=ax1.transAxes)

        ax2 = plt.subplot2grid((nrows, 3 * ncols), (irow, icol + 1),
                               aspect='equal')
        ax2.axis('off')
        #ax2.imshow(stamp-model_mog, **tim.ima)
        ax2.imshow(stamp - model_mog,
                   cmap='gray',
                   interpolation='nearest',
                   origin='lower',
                   vmin=mn,
                   vmax=mx)
        ax2.text(0.1,
                 0.9,
                 'MoG',
                 color='white',
                 horizontalalignment='left',
                 verticalalignment='top',
                 transform=ax2.transAxes)
        ax2.text(0.08,
                 0.08,
                 '{:.3f}'.format(mag_mog),
                 color='white',
                 horizontalalignment='left',
                 verticalalignment='bottom',
                 transform=ax2.transAxes)

        #ax2.set_title('{:.3f}, {:.2f}'.format(mag_psfex,chi2_psfex),fontsize=14)
        #ax2.set_title('{:.3f}, $\chi^{2}$={:.2f}'.format(mag_psfex,chi2_psfex))

        ax3 = plt.subplot2grid((nrows, 3 * ncols), (irow, icol + 2),
                               aspect='equal')
        ax3.axis('off')
        #ax3.imshow(stamp-model_psfex, **tim.ima)
        ax3.imshow(stamp - model_psfex,
                   cmap='gray',
                   interpolation='nearest',
                   origin='lower',
                   vmin=mn,
                   vmax=mx)
        ax3.text(0.1,
                 0.9,
                 'PSFEx',
                 color='white',
                 horizontalalignment='left',
                 verticalalignment='top',
                 transform=ax3.transAxes)
        ax3.text(0.08,
                 0.08,
                 '{:.3f}'.format(mag_psfex),
                 color='white',
                 horizontalalignment='left',
                 verticalalignment='bottom',
                 transform=ax3.transAxes)

        if istar == (nstar - 1):
            break
    fig.savefig(pngprefix + '-stargrid.png', bbox_inches='tight')
Exemple #3
0
def run_sed_matched_filters(SEDs,
                            bands,
                            detmaps,
                            detivs,
                            omit_xy,
                            targetwcs,
                            nsigma=5,
                            saturated_pix=None,
                            plots=False,
                            ps=None,
                            mp=None):
    '''
    Runs a given set of SED-matched filters.

    Parameters
    ----------
    SEDs : list of (name, sed) tuples
        The SEDs to run.  The `sed` values are lists the same length
        as `bands`.
    bands : list of string
        The band names of `detmaps` and `detivs`.
    detmaps : numpy array, float
        Detection maps for each of the listed `bands`.
    detivs : numpy array, float
        Inverse-variances of the `detmaps`.
    omit_xy : None, or (xx,yy) tuple
        Existing sources to avoid.
    targetwcs : WCS object
        WCS object to use to convert pixel values into RA,Decs for the
        returned Tractor PointSource objects.
    nsigma : float, optional
        Detection threshold
    saturated_pix : None or numpy array, boolean
        Passed through to sed_matched_detection.
        A map of pixels that are always considered "hot" when
        determining whether a new source touches hot pixels of an
        existing source.
    plots : boolean, optional
        Create plots?
    ps : PlotSequence object
        Create plots?
    mp : multiproc object
        Multiprocessing
        
    Returns
    -------
    Tnew : fits_table
        Table of new sources detected
    newcat : list of PointSource objects
        Newly detected objects, with positions and fluxes, as Tractor
        PointSource objects.
    hot : numpy array of bool
        "Hot pixels" containing sources.
        
    See also
    --------
    sed_matched_detection : run a single SED-matched filter.
    
    '''
    if omit_xy is not None:
        xx, yy = omit_xy
        n0 = len(xx)
    else:
        xx, yy = [], []
        n0 = 0

    H, W = detmaps[0].shape
    hot = np.zeros((H, W), bool)

    peaksn = []
    apsn = []

    for sedname, sed in SEDs:
        print('SED', sedname)
        if plots:
            pps = ps
        else:
            pps = None
        t0 = Time()
        sedhot, px, py, peakval, apval = sed_matched_detection(
            sedname,
            sed,
            detmaps,
            detivs,
            bands,
            xx,
            yy,
            nsigma=nsigma,
            saturated_pix=saturated_pix,
            ps=pps)
        print('SED took', Time() - t0)
        if sedhot is None:
            continue
        print(len(px), 'new peaks')
        hot |= sedhot
        # With an empty xx, np.append turns it into a double!
        xx = np.append(xx, px).astype(int)
        yy = np.append(yy, py).astype(int)

        peaksn.extend(peakval)
        apsn.extend(apval)

    # New peaks:
    peakx = xx[n0:]
    peaky = yy[n0:]

    if len(peakx) == 0:
        return None, None, None

    # Add sources for the new peaks we found
    pr, pd = targetwcs.pixelxy2radec(peakx + 1, peaky + 1)
    print('Adding', len(pr), 'new sources')
    # Also create FITS table for new sources
    Tnew = fits_table()
    Tnew.ra = pr
    Tnew.dec = pd
    Tnew.tx = peakx
    Tnew.ty = peaky
    assert (len(peaksn) == len(Tnew))
    assert (len(apsn) == len(Tnew))
    Tnew.peaksn = np.array(peaksn)
    Tnew.apsn = np.array(apsn)

    Tnew.itx = np.clip(np.round(Tnew.tx), 0, W - 1).astype(int)
    Tnew.ity = np.clip(np.round(Tnew.ty), 0, H - 1).astype(int)
    newcat = []
    for i, (r, d, x, y) in enumerate(zip(pr, pd, peakx, peaky)):
        fluxes = dict([(band, detmap[Tnew.ity[i], Tnew.itx[i]])
                       for band, detmap in zip(bands, detmaps)])
        newcat.append(
            PointSource(RaDecPos(r, d), NanoMaggies(order=bands, **fluxes)))

    return Tnew, newcat, hot
Exemple #4
0
    return I


if __name__ == '__main__':

    #(allp, i2magsA, cat) = unpickle_from_file('s2-260-A.pickle')

    (allp, i2mags, cat) = unpickle_from_file('s2-382.pickle')

    #print 'i2 mags A:', len(i2magsA)
    #print 'i2 mags:', len(i2mags)
    #i2mags = i2magsA

    from tractor.basics import NanoMaggies
    #print 'i2mags', i2mags
    i2mags = np.array([NanoMaggies(i=m).getMag('i') for m in i2mags])
    #print 'i2mags', mags

    #allbands = ['i2','u','g','r','i','z']
    allbands = ['i2', 'u', 'g', 'r', 'i', 'z', 'w1', 'w2', 'w3', 'w4']

    T = fits_table('cs82data/W4p1m1_i.V2.7A.swarp.cut.deVexp.fit', hdunum=2)
    #RA = 334.32
    #DEC = 0.315
    #sz = 0.12 * 3600.
    #S = sz / 3600.
    #ra0 ,ra1  = RA-S/2.,  RA+S/2.
    #dec0,dec1 = DEC-S/2., DEC+S/2.
    print 'Read', len(T), 'sources'
    T.ra = T.alpha_j2000
    T.dec = T.delta_j2000