def make_psf_mapcube(skydir, psf, outfile, npix=500, cdelt=0.01, rebin=1):
energies = psf.energies
nebin = len(energies)
k = utils.make_psf_kernel(psf, npix * rebin, cdelt / rebin)
if rebin > 1:
k = utils.rebin_map(k, nebin, npix, rebin)
w = wcs_utils.create_wcs(skydir, cdelt=cdelt,
crpix=npix / 2. + 0.5, naxis=3)
w.wcs.crpix[2] = 1
w.wcs.crval[2] = 10 ** energies[0]
w.wcs.cdelt[2] = energies[1] - energies[0]
w.wcs.ctype[2] = 'Energy'
ecol = fits.Column(name='Energy', format='D', array=10 ** energies)
hdu_energies = fits.BinTableHDU.from_columns([ecol], name='ENERGIES')
hdu_image = fits.PrimaryHDU(np.zeros((nebin, npix, npix)),
header=w.to_header())
hdu_image.data[...] = k
hdu_image.header['CUNIT3'] = 'MeV'
with fits.HDUList([hdu_image, hdu_energies]) as hdulist:
hdulist.writeto(outfile, overwrite=True)
def make_psf_mapcube(skydir, psf, outfile, npix=500, cdelt=0.01, rebin=1):
energies = psf.energies
nebin = len(energies)
k = utils.make_psf_kernel(psf, npix * rebin, cdelt / rebin)
if rebin > 1:
k = utils.rebin_map(k, nebin, npix, rebin)
w = wcs_utils.create_wcs(skydir,
cdelt=cdelt,
crpix=npix / 2. + 0.5,
naxis=3)
w.wcs.crpix[2] = 1
w.wcs.crval[2] = 10**energies[0]
w.wcs.cdelt[2] = energies[1] - energies[0]
w.wcs.ctype[2] = 'Energy'
ecol = fits.Column(name='Energy', format='D', array=10**energies)
hdu_energies = fits.BinTableHDU.from_columns([ecol], name='ENERGIES')
hdu_image = fits.PrimaryHDU(np.zeros((nebin, npix, npix)),
header=w.to_header())
hdu_image.data[...] = k
hdu_image.header['CUNIT3'] = 'MeV'
with fits.HDUList([hdu_image, hdu_energies]) as hdulist:
hdulist.writeto(outfile, overwrite=True)
def make_srcmap(skydir,
psf,
spatial_model,
sigma,
npix=500,
xpix=0.0,
ypix=0.0,
cdelt=0.01,
rebin=1,
psf_scale_fn=None):
"""Compute the source map for a given spatial model.
Parameters
----------
skydir : `~astropy.coordinates.SkyCoord`
psf : `~fermipy.irfs.PSFModel`
spatial_model : str
Spatial model.
sigma : float
Spatial size parameter for extended models.
xpix : float
Source position in pixel coordinates in X dimension.
ypix : float
Source position in pixel coordinates in Y dimension.
rebin : int
Factor by which the original map will be oversampled in the
spatial dimension when computing the model.
psf_scale_fn : callable
Function that evaluates the PSF scaling function.
Argument is energy in MeV.
"""
energies = psf.energies
nebin = len(energies)
if spatial_model == 'GaussianSource' or spatial_model == 'RadialGaussian':
k = utils.make_cgauss_kernel(psf, sigma, npix * rebin, cdelt / rebin,
xpix * rebin, ypix * rebin, psf_scale_fn)
elif spatial_model == 'DiskSource' or spatial_model == 'RadialDisk':
k = utils.make_cdisk_kernel(psf, sigma, npix * rebin, cdelt / rebin,
xpix * rebin, ypix * rebin, psf_scale_fn)
elif spatial_model == 'PSFSource' or spatial_model == 'PointSource':
k = utils.make_psf_kernel(psf, npix * rebin, cdelt / rebin,
xpix * rebin, ypix * rebin, psf_scale_fn)
else:
raise Exception('Unrecognized spatial model: %s' % spatial_model)
if rebin > 1:
k = utils.rebin_map(k, nebin, npix, rebin)
k *= psf.exp[:, np.newaxis, np.newaxis] * np.radians(cdelt)**2
return k