def _get_gals(self, mode, dx, dy):
# mode = self['Mode']
#Cen = galsim.Gaussian(half_light_radius=self['Cen']['hlr'],flux=self['Cen']['Flux'])
#Neigh = galsim.Exponential(half_light_radius=self['Neigh']['hlr'],flux=self['Neigh']['Flux'])
n = rng.uniform(low=0.5, high=4)
Cen = galsim.Sersic(n,
half_light_radius=self['Cen']['hlr'],
flux=self['Cen']['Flux'])
n = rng.uniform(low=0.5, high=4)
Neigh = galsim.Sersic(n,
half_light_radius=self['Neigh']['hlr'],
flux=self['Neigh']['Flux'])
Cen = Cen.shear(g1=np.random.normal(scale=0.02),
g2=np.random.normal(scale=0.02))
Neigh = Neigh.shear(g1=np.random.normal(scale=0.02),
g2=np.random.normal(scale=0.02))
#cen position
if self['Cen']['Pos'] == 'Fixed':
dx1, dy1 = self['Cen']['dx'], self['Cen']['dy']
elif self['Cen']['Pos'] == 'Rand_Circle':
r = self['Cen']['r']
theta = 2. * np.pi * np.random.random()
dx1, dy1 = r * np.cos(theta), r * np.sin(theta)
#neigh position
if self['Neigh']['Pos'] == 'Fixed':
dx2, dy2 = self['Neigh']['dx'], self['Neigh']['dy']
elif self['Neigh']['Pos'] == 'Rand_circle':
r = self['Neigh']['r']
theta = 2. * np.pi * np.random.random()
dx2, dy2 = r * np.cos(theta), r * np.sin(theta)
dx1 += np.random.uniform(low=-0.5, high=0.5)
dy1 += np.random.uniform(low=-0.5, high=0.5)
dx2 += np.random.uniform(low=-0.5, high=0.5)
dy2 += np.random.uniform(low=-0.5, high=0.5)
#Cen = Cen.shift(dx=dx1, dy=dy1)
#Neigh = Neigh.shift(dx=dx2, dy=dy2)
if mode == 'scarlet' or mode == 'minimof':
Cen = Cen.shift(dx=dx1, dy=dy1)
Neigh = Neigh.shift(dx=dx2, dy=dy2)
gals = [Cen, Neigh]
objs = galsim.Add(gals)
elif mode == 'control':
Cen = Cen.shift(dx=dx, dy=dy)
gals = [Cen]
objs = galsim.Add(gals)
dx1, dy1 = dx, dy
shear1, shear2 = self['Shear']['Shear1'], self['Shear']['Shear2']
#objs = objs.shear(g1=shear1, g2=shear2)
return objs, dx1, dy1, dx2, dy2
def test_add_flux_scaling():
"""Test flux scaling for Add.
"""
import time
t1 = time.time()
# decimal point to go to for parameter value comparisons
param_decimal = 12
# init with Gaussian and Exponential only (should be ok given last tests)
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj *= 2.
np.testing.assert_almost_equal(
obj.getFlux(), test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __imul__.")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj /= 2.
np.testing.assert_almost_equal(
obj.getFlux(), test_flux / 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __idiv__.")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = obj * 2.
# First test that original obj is unharmed... (also tests that .copy() is working)
np.testing.assert_almost_equal(
obj.getFlux(), test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __rmul__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.getFlux(), test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __rmul__ (result).")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = 2. * obj
# First test that original obj is unharmed... (also tests that .copy() is working)
np.testing.assert_almost_equal(
obj.getFlux(), test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __mul__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.getFlux(), test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __mul__ (result).")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = obj / 2.
# First test that original obj is unharmed... (also tests that .copy() is working)
np.testing.assert_almost_equal(
obj.getFlux(), test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __div__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.getFlux(), test_flux / 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __div__ (result).")
t2 = time.time()
print 'time for %s = %.2f'%(funcname(),t2-t1)
def test_autocorrelate():
"""Test that auto-correlation works the same as convolution with the mirror image of itself.
(See the Signal processing Section of http://en.wikipedia.org/wiki/Autocorrelation)
"""
import time
t1 = time.time()
# Use a function that is NOT two-fold rotationally symmetric, e.g. two different flux Gaussians
myGauss1 = galsim.SBGaussian(sigma=3., flux=4)
myGauss1.applyShift(-0.2, -0.4)
myGauss2 = (galsim.SBGaussian(sigma=6., flux=1.3))
myGauss2.applyShift(0.3, 0.3)
mySBP1 = galsim.SBAdd([myGauss1, myGauss2])
mySBP2 = galsim.SBAdd([myGauss1, myGauss2])
# Here we rotate by 180 degrees to create mirror image
mySBP2.applyRotation(180. * galsim.degrees)
myConv = galsim.SBConvolve([mySBP1, mySBP2])
myImg1 = galsim.ImageF(80, 80, scale=0.7)
myConv.draw(myImg1.view())
myAutoCorr = galsim.SBAutoCorrelate(mySBP1)
myImg2 = galsim.ImageF(80, 80, scale=0.7)
myAutoCorr.draw(myImg2.view())
printval(myImg1, myImg2)
np.testing.assert_array_almost_equal(
myImg1.array,
myImg2.array,
4,
err_msg=
"Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
+ "SBAutoCorrelate result")
# Repeat with the GSObject version of this:
obj1 = galsim.Gaussian(sigma=3., flux=4)
obj1.applyShift(-0.2, -0.4)
obj2 = galsim.Gaussian(sigma=6., flux=1.3)
obj2.applyShift(0.3, 0.3)
add1 = galsim.Add(obj1, obj2)
add2 = (galsim.Add(obj1, obj2)).createRotated(180. * galsim.degrees)
conv = galsim.Convolve([add1, add2])
conv.draw(myImg1)
corr = galsim.AutoCorrelate(add1)
corr.draw(myImg2)
printval(myImg1, myImg2)
np.testing.assert_array_almost_equal(
myImg1.array,
myImg2.array,
4,
err_msg=
"Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
+ "AutoCorrelate result")
# Test photon shooting.
do_shoot(corr, myImg2, "AutoCorrelate")
t2 = time.time()
print 'time for %s = %.2f' % (funcname(), t2 - t1)
def test_add_flux_scaling():
"""Test flux scaling for Add.
"""
# decimal point to go to for parameter value comparisons
param_decimal = 12
test_flux = 17.9
test_sigma = 1.8
test_scale = 1.9
# init with Gaussian and Exponential only (should be ok given last tests)
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj *= 2.
np.testing.assert_almost_equal(
obj.flux, test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __imul__.")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj /= 2.
np.testing.assert_almost_equal(
obj.flux, test_flux / 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __idiv__.")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = obj * 2.
# First test that original obj is unharmed...
np.testing.assert_almost_equal(
obj.flux, test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __rmul__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.flux, test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __rmul__ (result).")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = 2. * obj
# First test that original obj is unharmed...
np.testing.assert_almost_equal(
obj.flux, test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __mul__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.flux, test_flux * 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __mul__ (result).")
obj = galsim.Add([galsim.Gaussian(sigma=test_sigma, flux=test_flux * .5),
galsim.Exponential(scale_radius=test_scale, flux=test_flux * .5)])
obj2 = obj / 2.
# First test that original obj is unharmed...
np.testing.assert_almost_equal(
obj.flux, test_flux, decimal=param_decimal,
err_msg="Flux param inconsistent after __div__ (original).")
# Then test new obj2 flux
np.testing.assert_almost_equal(
obj2.flux, test_flux / 2., decimal=param_decimal,
err_msg="Flux param inconsistent after __div__ (result).")
def _get_band_obj(self, Cen, Neigh, cen_sed, neigh_sed):
mode = self['Mode']
if mode == 'scarlet' or mode == 'mof':
Cen = Cen * cen_sed
Neigh = Neigh * neigh_sed
gals = [Cen, Neigh]
objs = galsim.Add(gals)
elif mode == 'control':
Cen = Cen * cen_sed
gals = [Cen]
objs = galsim.Add(gals)
return objs
def _get_gals(self):
mode = self['Mode']
rng = self.rng
Cen = self._get_cen_model()
Neigh = self._get_nbr_model()
#cen position
if self['Cen']['Pos'] == 'Fixed':
dx1, dy1 = self['Cen']['dx'], self['Cen']['dy']
elif self['Cen']['Pos'] == 'Rand_Circle':
r = self['Cen']['r']
theta = 2. * np.pi * np.random.random()
dx1, dy1 = r * np.cos(theta), r * np.sin(theta)
#neigh position
if self['Neigh']['Pos'] == 'Fixed':
dx2, dy2 = self['Neigh']['dx'], self['Neigh']['dy']
elif self['Neigh']['Pos'] == 'Rand_circle':
r = self['Neigh']['r']
theta = 2. * np.pi * np.random.random()
dx2, dy2 = r * np.cos(theta), r * np.sin(theta)
dx1 += np.random.uniform(low=-0.5, high=0.5)
dy1 += np.random.uniform(low=-0.5, high=0.5)
dx2 += np.random.uniform(low=-0.5, high=0.5)
dy2 += np.random.uniform(low=-0.5, high=0.5)
Cen = Cen.shift(dx=dx1, dy=dy1)
Neigh = Neigh.shift(dx=dx2, dy=dy2)
if mode == 'scarlet' or mode == 'mof':
gals = [Cen, Neigh]
objs = galsim.Add(gals)
elif mode == 'control':
gals = [Cen]
objs = galsim.Add(gals)
shear_spec = self['Shear']
shear1, shear2 = shear_spec['Shear1'], shear_spec['Shear2']
objs = objs.shear(g1=shear1, g2=shear2)
if 'Extra_Shear' in shear_spec:
if 'shear+' in shear_spec['Extra_Shear']:
objs = objs.shear(g1=shear_spec['Extra_Shear']['shear+'],
g2=0.0)
elif 'shear-' in shear_spec['Extra_Shear']:
objs = objs.shear(g1=shear_spec['Extra_Shear']['shear-'],
g2=0.0)
return objs, dx1, dy1, dx2, dy2
def main():
for profile, exactGal, nComponents, maxRadius in PROFILES:
exactGal.applyShear(e1=E1, e2=E2)
psf = galsim.Gaussian(sigma=PSF_SIGMA)
exactObj = galsim.Convolve([exactGal, psf])
exactImage = exactObj.draw(dx=1.0)
exactImage.write(profile + "-exact.fits")
amplitudes, variances = lsst.shapelet.tractor.loadParameters(
profile, nComponents, maxRadius)
componentGals = []
for n, (amplitude, variance) in enumerate(zip(amplitudes, variances)):
componentGal = galsim.Gaussian(flux=amplitude,
sigma=GALAXY_RADIUS * variance**0.5)
componentGal.applyShear(e1=E1, e2=E2)
componentGals.append(componentGal)
if MAKE_COMPONENT_IMAGES:
componentObj = galsim.Convolve([componentGal, psf])
componentImage = galsim.ImageD(exactImage.bounds)
componentObj.draw(componentImage, dx=1.0)
componentImage.write("%s-approx-%0d.fits" % (profile, n))
approxGal = galsim.Add(componentGals)
approxObj = galsim.Convolve([approxGal, psf])
approxImage = galsim.ImageD(exactImage.bounds)
approxObj.draw(approxImage, dx=1.0)
approxImage.write(profile + "-approx.fits")
f1 = galsim.Add([
makeGaussian(flux=0.600000,
e1=0.09090909,
e2=0.36363636,
sigma=2.25810086),
makeGaussian(flux=0.400000,
e1=-0.11111111,
e2=-0.11111111,
sigma=2.98130750),
])
f2 = galsim.Add([
makeGaussian(flux=0.350000,
e1=-0.26315789,
e2=-0.21052632,
sigma=2.99069756),
makeGaussian(flux=0.650000,
e1=-0.12500000,
e2=0.12500000,
sigma=2.80606626),
])
f3 = galsim.Convolve([f1, f2])
image = galsim.ImageD(galsim.BoundsI(-20, 20, -20, 20))
f3.draw(image, dx=1.0)
image.write("gaussians.fits")
def test_autocorrelate():
"""Test that auto-correlation works the same as convolution with the mirror image of itself.
(See the Signal processing Section of http://en.wikipedia.org/wiki/Autocorrelation)
"""
dx = 0.7
myImg1 = galsim.ImageF(80, 80, scale=dx)
myImg1.setCenter(0, 0)
myImg2 = galsim.ImageF(80, 80, scale=dx)
myImg2.setCenter(0, 0)
# Use a function that is NOT two-fold rotationally symmetric, e.g. two different flux Gaussians
obj1 = galsim.Gaussian(sigma=3., flux=4).shift(-0.2, -0.4)
obj2 = galsim.Gaussian(sigma=6., flux=1.3).shift(0.3, 0.3)
add1 = galsim.Add(obj1, obj2)
# Here we rotate by 180 degrees to create mirror image
add2 = (galsim.Add(obj1, obj2)).rotate(180. * galsim.degrees)
conv = galsim.Convolve([add1, add2])
conv.drawImage(myImg1, method='no_pixel')
corr = galsim.AutoCorrelate(add1)
corr.drawImage(myImg2, method='no_pixel')
printval(myImg1, myImg2)
np.testing.assert_array_almost_equal(
myImg1.array,
myImg2.array,
4,
err_msg=
"Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
+ "AutoCorrelate result")
check_basic(conv, "AutoCorrelate")
# Test photon shooting.
do_shoot(corr, myImg2, "AutoCorrelate")
# Check picklability
do_pickle(corr, lambda x: x.drawImage(method='no_pixel'))
do_pickle(corr)
# Should raise an exception for invalid arguments
assert_raises(TypeError, galsim.AutoCorrelate)
assert_raises(TypeError, galsim.AutoCorrelate, myImg1)
assert_raises(TypeError, galsim.AutoCorrelate, [obj1])
assert_raises(TypeError, galsim.AutoCorrelate, obj1, obj2)
assert_raises(TypeError, galsim.AutoCorrelate, obj1, realspace=False)
assert_raises(TypeError, galsim.AutoCorrelation)
assert_raises(TypeError, galsim.AutoCorrelation, myImg1)
assert_raises(TypeError, galsim.AutoCorrelation, [obj1])
assert_raises(TypeError, galsim.AutoCorrelation, obj1, obj2)
assert_raises(TypeError, galsim.AutoCorrelation, obj1, realspace=False)
def _BuildAdd(config, key, base, ignore, gsparams, logger):
"""@brief Build a Sum object.
"""
req = {'items': list}
opt = {'flux': float}
# Only Check, not Get. We need to handle items a bit differently, since it's a list.
galsim.config.CheckAllParams(config, key, req=req, opt=opt, ignore=ignore)
gsobjects = []
items = config['items']
if not isinstance(items, list):
raise AttributeError("items entry for config.%s entry is not a list." %
type)
safe = True
for i in range(len(items)):
gsobject, safe1 = BuildGSObject(items, i, base, gsparams, logger)
# Skip items with flux=0
if 'flux' in items[i] and galsim.config.value.GetCurrentValue(
items[i], 'flux') == 0.:
if logger:
logger.debug('obj %d: Not including component with flux == 0',
base['obj_num'])
continue
safe = safe and safe1
gsobjects.append(gsobject)
if len(gsobjects) == 0:
raise ValueError("No valid items for %s" % key)
elif len(gsobjects) == 1:
gsobject = gsobjects[0]
else:
# Special: if the last item in a Sum doesn't specify a flux, we scale it
# to bring the total flux up to 1.
if ('flux' not in items[-1]) and all('flux' in item
for item in items[0:-1]):
sum = 0
for item in items[0:-1]:
sum += galsim.config.value.GetCurrentValue(item, 'flux')
f = 1. - sum
if (f < 0):
import warnings
warnings.warn(
"Automatically scaling the last item in Sum to make the total flux\n"
+
"equal 1 requires the last item to have negative flux = %f"
% f)
gsobjects[-1] = gsobjects[-1].withFlux(f)
if gsparams: gsparams = galsim.GSParams(**gsparams)
else: gsparams = None
gsobject = galsim.Add(gsobjects, gsparams=gsparams)
if 'flux' in config:
flux, safe1 = galsim.config.ParseValue(config, 'flux', base, float)
if logger:
logger.debug('obj %d: flux == %f', base['obj_num'], flux)
gsobject = gsobject.withFlux(flux)
safe = safe and safe1
return gsobject, safe
def _generate_bd(
hlr,
flux,
vary=False,
rng=None,
max_bulge_shift_frac=0.1, # fraction of hlr
max_bulge_rot=np.pi / 4,
):
if vary:
bulge_frac = _generate_bulge_frac(rng)
else:
bulge_frac = 0.5
disk_frac = (1.0 - bulge_frac)
bulge = DeVaucouleurs(half_light_radius=hlr, flux=flux * bulge_frac)
disk = Exponential(half_light_radius=hlr, flux=flux * disk_frac)
if vary:
bulge = _shift_bulge(rng, bulge, hlr, max_bulge_shift_frac)
if vary:
g1disk, g2disk = _generate_g1g2(rng)
g1bulge, g2bulge = g1disk, g2disk
if vary:
g1bulge, g2bulge = _rotate_bulge(rng, max_bulge_rot, g1bulge,
g2bulge)
bulge = bulge.shear(g1=g1bulge, g2=g2bulge)
disk = disk.shear(g1=g1disk, g2=g2disk)
return galsim.Add(bulge, disk)
def create_source(self, fractions, half_light_radius,
minor_major_axis_ratio, position_angle):
"""Create a model for the on-sky profile of a single source.
Size and shape parameter values for any component that is not
present (because its fraction is zero) are ignored.
Parameters
----------
fractions : array
Array of length 2 giving the disk and bulge fractions, respectively,
which must be in the range [0,1] (but this is not checked). If
their sum is less than one, the remainder is modeled as a point-like
component.
half_light_radius : array
Array of length 2 giving the disk and bulge half-light radii in
arcseconds, respectively.
minor_major_axis_ratio : array
Array of length 2 giving the dimensionless on-sky ellipse
minor / major axis ratio for the disk and bulge components,
respectively.
position_angle : array
Array of length 2 giving the position angle in degrees of the on-sky
disk and bluge ellipses, respectively. Angles are measured counter
clockwise relative to the +x axis.
Returns
-------
galsim.GSObject
A object representing the sum of all requested components with its
total flux normalized to one.
"""
# This is a no-op but still required to define the namespace.
import galsim
components = []
if fractions[0] > 0:
# Disk component
components.append(
galsim.Exponential(
flux=fractions[0],
half_light_radius=half_light_radius[0]).shear(
q=minor_major_axis_ratio[0],
beta=position_angle[0] * galsim.degrees))
if fractions[1] > 0:
components.append(
galsim.DeVaucouleurs(
flux=fractions[1],
half_light_radius=half_light_radius[1]).shear(
q=minor_major_axis_ratio[1],
beta=position_angle[1] * galsim.degrees))
star_fraction = 1 - fractions.sum()
if star_fraction > 0:
# Model a point-like source with a tiny (0.001 arcsec) Gaussian.
# TODO: sigma should be in arcsec here, not microns!
components.append(
galsim.Gaussian(flux=star_fraction,
sigma=1e-3 * self.image.scale))
# Combine the components and transform to focal-plane microns.
return galsim.Add(components, gsparams=self.gsparams)
def createSource(self, galaxyIndex, shifted=False, lensed=False):
"""
Returns a GalSim model of the source for the specified galaxy index with
optional centroid shifts and weak lensing distortion.
"""
params = self.getTruthCatalog()[galaxyIndex]
# Create the bulge component.
bulge = galsim.Sersic(flux=params['bulge_flux'],
half_light_radius=params['bulge_hlr'],
n=params['bulge_n'],
gsparams=Observation.getGSParams())
bulge.applyShear(q=params['bulge_q'],
beta=params['bulge_beta_radians'] * galsim.radians)
# Is there a disk component?
if params['disk_flux'] > 0:
disk = galsim.Exponential(flux=params['disk_flux'],
half_light_radius=params['disk_hlr'],
gsparams=Observation.getGSParams())
disk.applyShear(q=params['disk_q'],
beta=params['disk_beta_radians'] * galsim.radians)
source = galsim.Add(bulge, disk)
else:
source = bulge
# Apply optional lensing.
if lensed:
source = source.lens(g1=params['g1'],
g2=params['g2'],
mu=params['mu'])
# Apply optional centroid shift.
if shifted:
source = source.shift(dx=params['xshift'] * self.pixelScale,
dy=params['yshift'] * self.pixelScale)
return source
def whiten(self, profiles, image, config, base, logger):
"""
Whiten the noise on the stamp according to the existing noise in all the profiles.
"""
total = galsim.Add(profiles)
return super(BlendBuilder, self).whiten(total, image, config, base,
logger)
def _BuildAdd(config, base, ignore, gsparams, logger):
"""@brief Build a Sum object.
"""
req = {'items': list}
opt = {'flux': float}
# Only Check, not Get. We need to handle items a bit differently, since it's a list.
galsim.config.CheckAllParams(config, req=req, opt=opt, ignore=ignore)
gsobjects = []
items = config['items']
if not isinstance(items, list):
raise AttributeError("items entry for type=Add is not a list.")
safe = True
for i in range(len(items)):
gsobject, safe1 = BuildGSObject(items, i, base, gsparams, logger)
# Skip items with flux=0
if 'flux' in items[i] and galsim.config.GetCurrentValue(
'flux', items[i], float, base) == 0.:
logger.debug('obj %d: Not including component with flux == 0',
base.get('obj_num', 0))
continue
safe = safe and safe1
gsobjects.append(gsobject)
if len(gsobjects) == 0:
raise ValueError("No valid items for type=Add")
elif len(gsobjects) == 1:
gsobject = gsobjects[0]
else:
# Special: if the last item in a Sum doesn't specify a flux, we scale it
# to bring the total flux up to 1.
if ('flux' not in items[-1]) and all('flux' in item
for item in items[0:-1]):
sum_flux = 0
for item in items[0:-1]:
sum_flux += galsim.config.GetCurrentValue(
'flux', item, float, base)
f = 1. - sum_flux
if (f < 0):
logger.warning(
"Warning: Automatic flux for the last item in Sum (to make the total flux=1) "
"resulted in negative flux = %f for that item" % f)
logger.debug(
'obj %d: Rescaling final object in sum to have flux = %f',
base.get('obj_num', 0), f)
gsobjects[-1] = gsobjects[-1].withFlux(f)
if gsparams: gsparams = galsim.GSParams(**gsparams)
else: gsparams = None
gsobject = galsim.Add(gsobjects, gsparams=gsparams)
if 'flux' in config:
flux, safe1 = galsim.config.ParseValue(config, 'flux', base, float)
logger.debug('obj %d: flux == %f', base.get('obj_num', 0), flux)
gsobject = gsobject.withFlux(flux)
safe = safe and safe1
return gsobject, safe
def _generate_bdk(
hlr,
flux,
vary=False,
rng=None,
gsrng=None,
knots_hlr_frac=0.25,
max_knots_disk_frac=0.1, # fraction of disk light
max_bulge_shift_frac=0.1, # fraction of hlr
max_bulge_rot=np.pi / 4,
):
if vary:
bulge_frac = _generate_bulge_frac(rng)
else:
bulge_frac = 0.5
all_disk_frac = (1.0 - bulge_frac)
knots_hlr = knots_hlr_frac * hlr
if vary:
knots_sub_frac = _generate_knots_sub_frac(rng, max_knots_disk_frac)
else:
knots_sub_frac = max_knots_disk_frac
disk_frac = (1 - knots_sub_frac) * all_disk_frac
knots_frac = knots_sub_frac * all_disk_frac
bulge = DeVaucouleurs(half_light_radius=hlr, flux=flux * bulge_frac)
disk = Exponential(half_light_radius=hlr, flux=flux * disk_frac)
if gsrng is None:
# fixed galaxy, so fix the rng
gsrng = galsim.BaseDeviate(123)
knots = galsim.RandomKnots(
npoints=10,
half_light_radius=knots_hlr,
flux=flux * knots_frac,
rng=gsrng,
)
if vary:
bulge = _shift_bulge(rng, bulge, hlr, max_bulge_shift_frac)
if vary:
g1disk, g2disk = _generate_g1g2(rng)
g1bulge, g2bulge = g1disk, g2disk
if vary:
g1bulge, g2bulge = _rotate_bulge(rng, max_bulge_rot, g1bulge,
g2bulge)
bulge = bulge.shear(g1=g1bulge, g2=g2bulge)
disk = disk.shear(g1=g1disk, g2=g2disk)
knots = knots.shear(g1=g1disk, g2=g2disk)
return galsim.Add(bulge, disk, knots)
def test_autocorrelate():
"""Test that auto-correlation works the same as convolution with the mirror image of itself.
(See the Signal processing Section of http://en.wikipedia.org/wiki/Autocorrelation)
"""
import time
t1 = time.time()
dx = 0.7
myImg1 = galsim.ImageF(80, 80, scale=dx)
myImg1.setCenter(0, 0)
myImg2 = galsim.ImageF(80, 80, scale=dx)
myImg2.setCenter(0, 0)
# Use a function that is NOT two-fold rotationally symmetric, e.g. two different flux Gaussians
obj1 = galsim.Gaussian(sigma=3., flux=4).shift(-0.2, -0.4)
obj2 = galsim.Gaussian(sigma=6., flux=1.3).shift(0.3, 0.3)
add1 = galsim.Add(obj1, obj2)
# Here we rotate by 180 degrees to create mirror image
add2 = (galsim.Add(obj1, obj2)).rotate(180. * galsim.degrees)
conv = galsim.Convolve([add1, add2])
conv.drawImage(myImg1, method='no_pixel')
corr = galsim.AutoCorrelate(add1)
corr.drawImage(myImg2, method='no_pixel')
printval(myImg1, myImg2)
np.testing.assert_array_almost_equal(
myImg1.array,
myImg2.array,
4,
err_msg=
"Asymmetric sum of Gaussians convolved with mirror of self disagrees with "
+ "AutoCorrelate result")
# Test photon shooting.
do_shoot(corr, myImg2, "AutoCorrelate")
# Check picklability
do_pickle(corr.SBProfile, lambda x:
(repr(x.getObj()), x.isRealSpace(), x.getGSParams()))
do_pickle(corr, lambda x: x.drawImage(method='no_pixel'))
do_pickle(corr)
do_pickle(corr.SBProfile)
t2 = time.time()
print 'time for %s = %.2f' % (funcname(), t2 - t1)
def make_image(self, iobj, band=0, obsnum=0, include_nbrs=False):
"""
make an image for the given band and observation number
including nbrs is causing some trouble, probably due to
the object being way off the stamp (why does it work for
the fitter?)
"""
import galsim
res = self.get_result()
pars = res['pars']
obs = self.list_of_obs[iobj][band][obsnum]
meta = obs.meta
psf_meta = obs.psf.meta
band_pars = self.get_object_band_pars(
pars,
iobj,
band,
)
central_model = self._make_fully_shifted_model(band_pars, obs)
if include_nbrs:
maxrad = self._get_maxrad(obs)
nbr_models = self._get_nbr_models(
iobj,
pars,
meta,
band,
maxrad,
obs,
)
else:
nbr_models = []
if len(nbr_models) > 0:
all_models = [central_model] + nbr_models
total_model = galsim.Add(
all_models,
gsparams=self._gsp,
)
else:
total_model = central_model
total_model = galsim.Convolve(
total_model,
psf_meta['ii'],
gsparams=self._gsp,
)
image = meta['model'].copy()
self._do_draw(obs, total_model, image)
return image.array
def make_bdf(half_light_radius=None,
flux=None,
fracdev=None,
trunc=0.0,
gsparams=None):
"""
a bulge+disk maker for equal hlr for bulge and disk
Parameters
----------
half_light_radius: float
hlr
flux: float
Total flux in the profile
fracdev: float
fraction of light in the bulge
"""
import galsim
assert half_light_radius is not None, 'send half_light_ratio'
assert flux is not None, 'send flux'
assert fracdev is not None, 'send fracdev'
if trunc > 0:
flux_untruncated = True
else:
flux_untruncated = False
"""
bulge = galsim.DeVaucouleurs(
half_light_radius=half_light_radius,
flux=fracdev,
flux_untruncated=flux_untruncated ,
trunc=trunc,
gsparams=gsparams,
)
"""
bulge = galsim.Sersic(
n=2,
half_light_radius=half_light_radius,
flux=fracdev,
flux_untruncated=flux_untruncated,
trunc=trunc,
gsparams=gsparams,
)
disk = galsim.Exponential(
half_light_radius=half_light_radius,
flux=(1 - fracdev),
gsparams=gsparams,
)
return galsim.Add(
bulge,
disk,
gsparams=gsparams,
).withFlux(flux)
def star2gs(self, index, gsparams):
# Convert from dict to actual GsParams object
# TODO: Currently fails if gsparams isn't passed!
if gsparams: gsp = galsim.GSParams(**gsparams)
else: gsp = None
# List of individual band GSObjects
gsobjects = []
# Iterate over all desired bands
for band in self.bands:
if self.data_version == 'y3v02':
# Needed for all mag calculations
gmag = self.catalog['g_Corr'][index]
# Grab current band magnitude
if band == 'g':
mag = gmag
elif band == 'r':
mag = gmag - self.catalog['gr_Corr'][index]
elif band == 'i':
mag = gmag - self.catalog['gr_Corr'][index] - self.catalog[
'ri_Corr'][index]
elif band == 'z':
mag = gmag - self.catalog['gr_Corr'][index] - self.catalog['ri_Corr'][index] \
- self.catalog['iz_Corr'][index]
else:
raise ValueError(
'Band {} is not an allowed band input '.format(band) +
'for data_version of {}!'.format(self.data_version))
# Now convert to flux
flux = np.power(10.0, 0.4 * (self.zeropoint - mag))
# (star cats calibrated at zp=30)
# NOTE: Will just use `scale_flux` parameter in galsim config for now
# flux_factor = ...
# Stars are treated as a delta function, to be convolved w/ set PSF
star = galsim.DeltaFunction(flux)
else:
# Should already be checked by this point, but just to be safe:
raise ValueError(
'There is no implementation for `star2gs` for data_version '
+ 'of {}'.format(self.data_version))
# Add galaxy in given band to list
gsobjects.append(star)
# NOTE: If multiple bands were passed, the fluxes are simply added together.
gs_star = galsim.Add(gsobjects)
return gs_star
def test_gsparams():
"""Test withGSParams with some non-default gsparams
"""
obj1 = galsim.Exponential(half_light_radius=1.7)
obj2 = galsim.Pixel(scale=0.2)
gsp = galsim.GSParams(folding_threshold=1.e-4,
maxk_threshold=1.e-4,
maximum_fft_size=1.e4)
gsp2 = galsim.GSParams(folding_threshold=1.e-2, maxk_threshold=1.e-2)
sum = galsim.Sum(obj1, obj2)
sum1 = sum.withGSParams(gsp)
assert sum.gsparams == galsim.GSParams()
assert sum1.gsparams == gsp
assert sum1.obj_list[0].gsparams == gsp
assert sum1.obj_list[1].gsparams == gsp
sum2 = galsim.Sum(obj1.withGSParams(gsp), obj2.withGSParams(gsp))
sum3 = galsim.Sum(galsim.Exponential(half_light_radius=1.7, gsparams=gsp),
galsim.Pixel(scale=0.2))
sum4 = galsim.Add(obj1, obj2, gsparams=gsp)
assert sum != sum1
assert sum1 == sum2
assert sum1 == sum3
assert sum1 == sum4
print('stepk = ', sum.stepk, sum1.stepk)
assert sum1.stepk < sum.stepk
print('maxk = ', sum.maxk, sum1.maxk)
assert sum1.maxk > sum.maxk
sum5 = galsim.Add(obj1, obj2, gsparams=gsp, propagate_gsparams=False)
assert sum5 != sum4
assert sum5.gsparams == gsp
assert sum5.obj_list[0].gsparams == galsim.GSParams()
assert sum5.obj_list[1].gsparams == galsim.GSParams()
sum6 = sum5.withGSParams(gsp2)
assert sum6 != sum5
assert sum6.gsparams == gsp2
assert sum6.obj_list[0].gsparams == galsim.GSParams()
assert sum6.obj_list[1].gsparams == galsim.GSParams()
def make_galsim_object(self, gsparams=None):
'''
Make a galsim representation for the gaussian mixture.
NOTE: The only difference from Erin's original code is the type checking and passing
of gsparams. This is especially useful for increasing fft sizes.
'''
# Accept optional gsparams for GSObject construction
if gsparams and (type(gsparams) is not galsim._galsim.GSParams):
if type(gsparams) is dict:
# Convert to actual gsparams object
gsparams = galsim.GSParams(**gsparams)
else:
raise TypeError(
'Only `dict` and `galsim.GSParam` types allowed for'
'gsparams; input has {} type.'.format(type(gsparams)))
data = self._get_gmix_data()
row, col = self.get_cen()
gsobjects = []
for i in xrange(len(self)):
flux = data['p'][i]
T = data['irr'][i] + data['icc'][i]
# assert(T!=0.0)
if T == 0:
# TODO: Explore this issue more! T is being stored as nonzero -
# what is causing this?
continue
e1 = (data['icc'][i] - data['irr'][i]) / T
e2 = 2.0 * data['irc'][i] / T
rowshift = data['row'][i] - row
colshift = data['col'][i] - col
g1, g2 = ngmix.shape.e1e2_to_g1g2(e1, e2)
Tround = ngmix.moments.get_Tround(T, g1, g2)
sigma_round = np.sqrt(Tround / 2.0)
gsobj = galsim.Gaussian(flux=flux,
sigma=sigma_round,
gsparams=gsparams)
gsobj = gsobj.shear(g1=g1, g2=g2)
gsobj = gsobj.shift(colshift, rowshift)
gsobjects.append(gsobj)
gs_obj = galsim.Add(gsobjects)
return gs_obj
def _get_bd_model(self, spec):
rng = self.rng
flux = spec['Flux']
fracdev = rng.uniform(low=0.0, high=1.0)
bulge_flux = fracdev * flux
disk_flux = (1.0 - fracdev) * flux
disk_hlr = spec['hlr']
if 'bulge_size_factor' in spec:
frange = spec['bulge_size_factor']['range']
bulge_hlr = disk_hlr * rng.uniform(
low=frange[0],
high=frange[1],
)
else:
bulge_hlr = disk_hlr
if 'knots' in spec:
disk_flux, knot_flux = self._split_flux_with_knots(spec, disk_flux)
disk = galsim.Exponential(
half_light_radius=disk_hlr,
flux=disk_flux,
)
bulge = galsim.DeVaucouleurs(
half_light_radius=bulge_hlr,
flux=bulge_flux,
)
if 'knots' in spec:
knots = self._get_knots(spec, disk_hlr, knot_flux)
disk = galsim.Add([disk, knots])
disk = self._add_ellipticity(disk, spec)
bulge = self._add_ellipticity(bulge, spec)
return galsim.Add([disk, bulge])
def doubleSersic(xcen1,
ycen1,
flux1,
reff1,
nser1,
q1,
pa1,
xcen2,
ycen2,
flux2,
reff2,
nser2,
q2,
pa2,
nx,
ny,
psf=None,
scale=1.0,
exptime=1.0,
trunc=0,
max_fft=None):
"""Generate image for double Sersic component."""
ser = galsim.Add([
galsim.Sersic(
n=nser1,
half_light_radius=reff1,
flux=(flux1 * exptime),
trunc=trunc).shear(q=q1, beta=(0.0 * galsim.degrees)).rotate(
(90.0 - pa1) * galsim.degrees).shift((xcen1 - (nx / 2.0)),
(ycen1 - (ny / 2.0))),
galsim.Sersic(
n=nser2,
half_light_radius=reff2,
flux=(flux2 * exptime),
trunc=trunc).shear(q=q2, beta=(0.0 * galsim.degrees)).rotate(
(90.0 - pa2) * galsim.degrees).shift((xcen2 - (nx / 2.0)),
(ycen2 - (ny / 2.0)))
])
if psf is not None:
if max_fft is not None:
gsparams = galsim.GSParams(maximum_fft_size=max_fft)
return (galsim.Convolve([ser, psf], gsparams=gsparams).drawImage(
nx=nx, ny=ny, method='no_pixel', scale=scale)).array
else:
return (galsim.Convolve([ser, psf]).drawImage(nx=nx,
ny=ny,
method='no_pixel',
scale=scale)).array
else:
return (ser.drawImage(nx=nx, ny=ny, method='no_pixel',
scale=scale)).array
def __init__(self, identifier, redshift, ab_magnitude, ri_color,
cosmic_shear_g1, cosmic_shear_g2, dx_arcsecs, dy_arcsecs,
beta_radians, disk_flux, disk_hlr_arcsecs, disk_q, bulge_flux,
bulge_hlr_arcsecs, bulge_q, agn_flux):
self.identifier = identifier
self.redshift = redshift
self.ab_magnitude = ab_magnitude
self.ri_color = ri_color
self.dx_arcsecs = dx_arcsecs
self.dy_arcsecs = dy_arcsecs
self.cosmic_shear_g1 = cosmic_shear_g1
self.cosmic_shear_g2 = cosmic_shear_g2
components = []
# Initialize second-moments tensor. Note that we can only add the tensors for the
# n = 1,4 components, as we do below, since they have the same centroid.
self.second_moments = np.zeros((2, 2))
total_flux = disk_flux + bulge_flux + agn_flux
self.disk_fraction = disk_flux / total_flux
self.bulge_fraction = bulge_flux / total_flux
if disk_flux > 0:
disk = galsim.Exponential(
flux=disk_flux, half_light_radius=disk_hlr_arcsecs).shear(
q=disk_q, beta=beta_radians * galsim.radians)
components.append(disk)
self.second_moments += self.disk_fraction * sersic_second_moments(
n=1, hlr=disk_hlr_arcsecs, q=disk_q, beta=beta_radians)
if bulge_flux > 0:
bulge = galsim.DeVaucouleurs(
flux=bulge_flux, half_light_radius=bulge_hlr_arcsecs).shear(
q=bulge_q, beta=beta_radians * galsim.radians)
components.append(bulge)
self.second_moments += self.bulge_fraction * sersic_second_moments(
n=1, hlr=bulge_hlr_arcsecs, q=bulge_q, beta=beta_radians)
# GalSim does not currently provide a "delta-function" component to model the AGN
# so we use a very narrow Gaussian. See this GalSim issue for details:
# https://github.com/GalSim-developers/GalSim/issues/533
if agn_flux > 0:
agn = galsim.Gaussian(flux=agn_flux, sigma=1e-8)
components.append(agn)
# Combine the components into our final profile.
self.profile = galsim.Add(components)
# Apply transforms to build the final model.
self.model = self.get_transformed_model()
# Shear the second moments, if necessary.
if self.cosmic_shear_g1 != 0 or self.cosmic_shear_g2 != 0:
self.second_moments = sheared_second_moments(
self.second_moments, self.cosmic_shear_g1,
self.cosmic_shear_g2)
def _get_images(self):
"""
get images without noise for each band
"""
import galsim
gmodels = []
rmodels = []
imodels = []
odlist = []
for i in range(self['objects']['nobj']):
band_models, odata = self._get_convolved_models()
gmodels.append(band_models[0])
rmodels.append(band_models[1])
imodels.append(band_models[2])
odlist.append(odata)
band_models = [
galsim.Add(gmodels),
galsim.Add(rmodels),
galsim.Add(imodels),
]
iconf = self['image']
ny, nx = [iconf['dim_pixels']] * 2
band_images = []
for model in band_models:
image = model.drawImage(
nx=nx,
ny=ny,
scale=iconf['pixel_scale'],
).array
band_images.append(image)
obj_data = eu.numpy_util.combine_arrlist(odlist)
return band_images, obj_data
def galSimAdd(galObjList, size=0, scale=1.0, method="auto", returnArr=False):
"""
Just add a list of GSObjs together using GalSim
Make sure all elements in the input list are GSObjs
"""
if len(galObjList) < 2:
raise Exception("Should be more than one GSObjs to add !")
outObj = galsim.Add(galObjList)
if returnArr:
outArr = galSimDrawImage(outObj, size=size, scale=scale, method=method)
return outArr
else:
return outObj
def _BuildAdd(config, key, base, ignore, gsparams):
"""@brief Build an Add object
"""
req = {'items': list}
opt = {'flux': float}
# Only Check, not Get. We need to handle items a bit differently, since it's a list.
galsim.config.CheckAllParams(config, key, req=req, opt=opt, ignore=ignore)
gsobjects = []
items = config['items']
if not isinstance(items, list):
raise AttributeError("items entry for config.%s entry is not a list." %
type)
safe = True
for i in range(len(items)):
gsobject, safe1 = BuildGSObject(items, i, base, gsparams)
safe = safe and safe1
gsobjects.append(gsobject)
#print 'After built component items for ',type,' safe = ',safe
# Special: if the last item in a Sum doesn't specify a flux, we scale it
# to bring the total flux up to 1.
if ('flux' not in items[-1]) and all('flux' in item
for item in items[0:-1]):
sum = 0
for item in items[0:-1]:
sum += galsim.config.value.GetCurrentValue(item, 'flux')
#print 'sum = ',sum
f = 1. - sum
#print 'f = ',f
if (f < 0):
import warnings
warnings.warn(
"Automatically scaling the last item in Sum to make the total flux\n"
+ "equal 1 requires the last item to have negative flux = %f" %
f)
gsobjects[-1].setFlux(f)
if gsparams: gsparams = galsim.GSParams(**gsparams)
else: gsparams = None
gsobject = galsim.Add(gsobjects, gsparams=gsparams)
if 'flux' in config:
flux, safe1 = galsim.config.ParseValue(config, 'flux', base, float)
#print 'flux = ',flux
gsobject.setFlux(flux)
safe = safe and safe1
return gsobject, safe
def add_lumps(self, n_regions, frac_gal_flux=0.05, frac_r_e=1.0,
**kwargs):
flux = self.gal.flux * frac_gal_flux
r_e = self.pars.r_e.to('arcsec') * frac_r_e
PA = self.pars.PA.value
ell = self.pars.ell
n = self.pars.n
lumps = HIIRegions(
n_regions=n_regions, flux=flux, PA=PA, r_e=r_e, ell=ell,
sersic_n=n, **kwargs)
self.gal = self.gal.withFlux(self.gal.flux * (1-frac_gal_flux))
self.gal = galsim.Add([self.gal, lumps])
self._original_gal = self.gal
def add_point_sources(self, n_points, frac_gal_flux=0.05, frac_r_e=1.0,
total_flux=None, point_fwhm=None):
r_e = self.pars.r_e.to('arcsec').value * frac_r_e
flux = total_flux if total_flux else self.gal.flux * frac_gal_flux
points = galsim.RandomWalk(n_points, half_light_radius=r_e, flux=flux)
points = points.shear(q=self.pars.b_a, beta=(0.0 * galsim.degrees))
points = points.rotate(
self.pars.PA.to('degree').value * galsim.degrees)
if total_flux is None:
self.gal = self.gal.withFlux(self.gal.flux * (1-frac_gal_flux))
if point_fwhm is not None:
point_psf = galsim.Gaussian(
flux=1.0, fwhm=point_fwhm.to('arcsec').value)
points = galsim.Convolve([points, point_psf])
self.gal = galsim.Add([self.gal, points])
self._original_gal = self.gal
def render_galaxy(
self,
galaxy_params: Tensor,
psf: galsim.GSObject,
slen: int,
offset: Optional[Tensor] = None,
) -> Tensor:
assert offset is None or offset.shape == (2, )
if isinstance(galaxy_params, Tensor):
galaxy_params = galaxy_params.cpu().detach()
total_flux, disk_frac, beta_radians, disk_q, a_d, bulge_q, a_b = galaxy_params
bulge_frac = 1 - disk_frac
disk_flux = total_flux * disk_frac
bulge_flux = total_flux * bulge_frac
components = []
if disk_flux > 0:
b_d = a_d * disk_q
disk_hlr_arcsecs = np.sqrt(a_d * b_d)
disk = galsim.Exponential(
flux=disk_flux, half_light_radius=disk_hlr_arcsecs).shear(
q=disk_q,
beta=beta_radians * galsim.radians,
)
components.append(disk)
if bulge_flux > 0:
b_b = bulge_q * a_b
bulge_hlr_arcsecs = np.sqrt(a_b * b_b)
bulge = galsim.DeVaucouleurs(
flux=bulge_flux, half_light_radius=bulge_hlr_arcsecs).shear(
q=bulge_q, beta=beta_radians * galsim.radians)
components.append(bulge)
galaxy = galsim.Add(components)
gal_conv = galsim.Convolution(galaxy, psf)
offset = offset if offset is None else offset.numpy()
image = gal_conv.drawImage(nx=slen,
ny=slen,
method="auto",
scale=self.pixel_scale,
offset=offset)
return torch.from_numpy(image.array).reshape(1, slen, slen)
