def fake_focalplane():
"""Create a set of fake detectors.
This generates 7 pixels (14 dets) in a hexagon layout at the boresight
and with a made up polarization orientation.
Args:
None
Returns:
(dict): dictionary of detectors and their properties.
"""
zaxis = np.array([0, 0, 1.0])
samplerate = 20.0
epsilon = 0.0
net = 1.0
fmin = 0.0
alpha = 1.0
fknee = 0.05
fwhm = 30.0
npix = 7
ndet = 2 * npix
pol_A = hex_pol_angles_qu(npix)
pol_B = hex_pol_angles_qu(npix, offset=90.0)
dets_A = hex_layout(npix, 3.0, "", "", pol_A)
dets_B = hex_layout(npix, 3.0, "", "", pol_B)
dets = dict()
for p in range(npix):
pstr = "{:01d}".format(p)
for d, layout in zip(["A", "B"], [dets_A, dets_B]):
props = dict()
props["quat"] = layout[pstr]["quat"]
props["epsilon"] = epsilon
props["rate"] = samplerate
props["alpha"] = alpha
props["NET"] = net
props["fmin"] = fmin
props["fknee"] = fknee
props["fwhm_arcmin"] = fwhm
dname = "{}{}".format(pstr, d)
dets[dname] = props
return dets
def fake_focalplane():
"""
Make a fake focalplane geometry.
This function returns a fake hexagonal focalplane with 19 pixels
and 2 detectors at each position. The spacing is set to fill the
field of view.
"""
npix = 19
# 5' beam
fwhm = 5.0 / 60.0
# 5 degree FOV...
fov = 5.0
# ...converted to size of hexagon
angwidth = fov * np.cos(30.0 * np.pi / 180.0)
# Alternating polarization orientations
Apol = tt.hex_pol_angles_qu(npix, offset=0.0)
Bpol = tt.hex_pol_angles_qu(npix, offset=90.0)
# Build a simple hexagon layout
Adets = tt.hex_layout(npix, 100.0, angwidth, fwhm, "fake_", "A", Apol)
Bdets = tt.hex_layout(npix, 100.0, angwidth, fwhm, "fake_", "B", Bpol)
# Combine into a single dictionary
dets = Adets.copy()
dets.update(Bdets)
# Give each detector the same fake noise properties
for indx, d in enumerate(sorted(dets.keys())):
# 50mHz knee frequency
dets[d]["fknee"] = 0.050
# High pass "plateau" to avoid blow-up at very low f
dets[d]["fmin"] = 1.0e-5
# Exponent
dets[d]["alpha"] = 1.0
# Sensitivity
dets[d]["NET"] = 20.0e-6
# Unique index for reproducibility of simulations
dets[d]["index"] = indx
return dets
def main():
parser = argparse.ArgumentParser(
description="Simulate fake hexagonal focalplane.",
fromfile_prefix_chars='@')
parser.add_argument("--minpix",
required=False,
type=int,
default=100,
help="minimum number of pixels to use")
parser.add_argument("--out",
required=False,
default="fp_fake",
help="Root name of output pickle file")
parser.add_argument("--fwhm",
required=False,
type=float,
default=5.0,
help="beam FWHM in arcmin")
parser.add_argument("--fwhm_sigma",
required=False,
type=float,
default=0,
help="Relative beam FWHM distribution width")
parser.add_argument("--fov",
required=False,
type=float,
default=5.0,
help="Field of View in degrees")
parser.add_argument("--psd_fknee",
required=False,
type=float,
default=0.05,
help="Detector noise model f_knee in Hz")
parser.add_argument("--psd_NET",
required=False,
type=float,
default=60.0e-6,
help="Detector noise model NET in K*sqrt(sec)")
parser.add_argument("--psd_alpha",
required=False,
type=float,
default=1.0,
help="Detector noise model slope")
parser.add_argument("--psd_fmin",
required=False,
type=float,
default=1.0e-5,
help="Detector noise model f_min in Hz")
parser.add_argument("--bandcenter_ghz",
required=False,
type=float,
help="Band center frequency [GHz]")
parser.add_argument("--bandcenter_sigma",
required=False,
type=float,
default=0,
help="Relative band center distribution width")
parser.add_argument("--bandwidth_ghz",
required=False,
type=float,
help="Bandwidth [GHz]")
parser.add_argument("--bandwidth_sigma",
required=False,
type=float,
default=0,
help="Relative bandwidth distribution width")
parser.add_argument("--random_seed",
required=False,
type=np.int,
default=123456,
help="Random number generator seed for randomized "
"detector parameters")
args = timing.add_arguments_and_parse(parser, timing.FILE(noquotes=True))
# Guard against being called with multiple processes
if MPI.COMM_WORLD.rank == 0:
# Make one big hexagon layout at the center of the focalplane.
# Compute the number of pixels that is at least the number requested.
test = args.minpix - 1
nrings = 0
while (test - 6 * nrings) > 0:
test -= 6 * nrings
nrings += 1
npix = 1
for r in range(1, nrings + 1):
npix += 6 * r
print("using {} pixels ({} detectors)".format(npix, npix * 2))
# Translate the field-of-view into distance between flag sides
angwidth = args.fov * np.cos(30 * degree)
Apol = tt.hex_pol_angles_qu(npix, offset=0.0)
Bpol = tt.hex_pol_angles_qu(npix, offset=90.0)
Adets = tt.hex_layout(npix, angwidth, "fake_", "A", Apol)
Bdets = tt.hex_layout(npix, angwidth, "fake_", "B", Bpol)
dets = Adets.copy()
dets.update(Bdets)
np.random.seed(args.random_seed)
for indx, d in enumerate(sorted(dets.keys())):
dets[d]["fknee"] = args.psd_fknee
dets[d]["fmin"] = args.psd_fmin
dets[d]["alpha"] = args.psd_alpha
dets[d]["NET"] = args.psd_NET
# This is in degrees, but the input is in arcmin.
dets[d]["fwhm_deg"] = (args.fwhm / 60.0) \
* (1 + np.random.randn()*args.fwhm_sigma)
# This is a fixed value, in arcmin.
dets[d]["fwhm"] = args.fwhm
if args.bandcenter_ghz:
dets[d]["bandcenter_ghz"] \
= args.bandcenter_ghz * (1+np.random.randn()*args.bandcenter_sigma)
if args.bandwidth_ghz:
dets[d]["bandwidth_ghz"] \
= args.bandwidth_ghz * (1+np.random.randn()*args.bandwidth_sigma)
dets[d]["index"] = indx
outfile = "{}_{}".format(args.out, npix)
qdets = {x: y["quat"] for x, y in dets.items()}
beams = {x: (60.0 * y["fwhm_deg"]) for x, y in dets.items()}
tt.plot_focalplane(qdets,
args.fov,
args.fov,
"{}.png".format(outfile),
fwhm=beams)
with open("{}.pkl".format(outfile), "wb") as p:
pickle.dump(dets, p)
return
def fake_focalplane(
samplerate: float = 20.,
epsilon: float = 0.,
net: float = 1.,
fmin: float = 0.,
alpha: float = 1.,
fknee: float = 0.05,
fwhm: float = 30.,
npix: int = 7,
fov: float = 3.,
) -> Dict[str, Union[float, np.ndarray]]:
"""Create a set of fake detectors.
This generates 7 pixels (14 dets) in a hexagon layout at the boresight
and with a made up polarization orientation.
This function is copied from TOAST workshop with the following license:
BSD 2-Clause License
Copyright (c) 2019, hpc4cmb
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""
pol_A = hex_pol_angles_qu(npix)
pol_B = hex_pol_angles_qu(npix, offset=90.0)
dets_A = hex_layout(npix, fov, "", "", pol_A)
dets_B = hex_layout(npix, fov, "", "", pol_B)
dets = {}
for p in range(npix):
pstr = "{:01d}".format(p)
for d, layout in zip(["A", "B"], [dets_A, dets_B]):
props = dict()
props["quat"] = layout[pstr]["quat"]
props["epsilon"] = epsilon
props["rate"] = samplerate
props["alpha"] = alpha
props["NET"] = net
props["fmin"] = fmin
props["fknee"] = fknee
props["fwhm_arcmin"] = fwhm
dname = "{}{}".format(pstr, d)
dets[dname] = props
return dets
#!/usr/bin/env python3
from toast.mpi import MPI
from toast.tod.sim_tod import TODSatellite
from toast.tod import hex_layout, hex_pol_angles_qu
# Create a simple hex focalplane. This number of detectors might be typical
# for the number per process in a full-machine run.
npix = 37
pol = hex_pol_angles_qu(npix)
fp = hex_layout(npix, 1.0, "det", "", pol)
print(fp, flush=True)
# Write this out to a simple text format
with open("focalplane.txt", "w") as f:
for det, props in fp.items():
q = props["quat"]
f.write("{} {:0.15e} {:0.15e} {:0.15e} {:0.15e}\n".format(
det, q[0], q[1], q[2], q[3]))
# Use a typical sample rate and simulate data for one observation. We can
# then repeat this for a typical number of observations to get the right
# data volume.
rate = 100.0
samples = 180000
tod = TODSatellite(MPI.COMM_WORLD,
fp,
samples,
npix = 1
for r in range(1, nrings + 1):
npix += 6 * r
print("using {} pixels ({} detectors)".format(npix, npix * 2))
fwhm = args.fwhm / 60.0
width = 100.0
# Translate the field-of-view into distance between flag sides
angwidth = args.fov * np.cos(30 * degree)
Apol = tt.hex_pol_angles_qu(npix, offset=0.0)
Bpol = tt.hex_pol_angles_qu(npix, offset=90.0)
Adets = tt.hex_layout(npix, width, angwidth, fwhm, "fake_", "A", Apol)
Bdets = tt.hex_layout(npix, width, angwidth, fwhm, "fake_", "B", Bpol)
dets = Adets.copy()
dets.update(Bdets)
np.random.seed(args.random_seed)
for indx, d in enumerate(sorted(dets.keys())):
dets[d]["fknee"] = args.psd_fknee
dets[d]["fmin"] = args.psd_fmin
dets[d]["alpha"] = args.psd_alpha
dets[d]["NET"] = args.psd_NET
dets[d]["fwhm_deg"] = fwhm \
* (1 + np.random.randn()*args.fwhm_sigma)
dets[d]["fwhm"] = dets[d]["fwhm_deg"] # Support legacy code
def main():
parser = argparse.ArgumentParser(
description="Simulate fake hexagonal focalplane.",
fromfile_prefix_chars='@')
parser.add_argument( "--minpix", required=False, type=int, default=100,
help="minimum number of pixels to use" )
parser.add_argument( "--out", required=False, default="fp_fake",
help="Root name of output pickle file" )
parser.add_argument( "--fwhm", required=False, type=float, default=5.0,
help="beam FWHM in arcmin" )
parser.add_argument( "--fwhm_sigma", required=False, type=float, default=0,
help="Relative beam FWHM distribution width" )
parser.add_argument( "--fov", required=False, type=float, default=5.0,
help="Field of View in degrees" )
parser.add_argument( "--psd_fknee", required=False, type=float,
default=0.05, help="Detector noise model f_knee in Hz" )
parser.add_argument( "--psd_NET", required=False, type=float,
default=60.0e-6, help="Detector noise model NET in K*sqrt(sec)" )
parser.add_argument( "--psd_alpha", required=False, type=float,
default=1.0, help="Detector noise model slope" )
parser.add_argument( "--psd_fmin", required=False, type=float,
default=1.0e-5, help="Detector noise model f_min in Hz" )
parser.add_argument( "--bandcenter_ghz", required=False, type=float,
help="Band center frequency [GHz]" )
parser.add_argument( "--bandcenter_sigma", required=False, type=float,
default=0, help="Relative band center distribution width" )
parser.add_argument( "--bandwidth_ghz", required=False, type=float,
help="Bandwidth [GHz]" )
parser.add_argument( "--bandwidth_sigma", required=False, type=float,
default=0, help="Relative bandwidth distribution width" )
parser.add_argument( "--random_seed", required=False, type=np.int,
default=123456, help="Random number generator seed for randomized "
"detector parameters" )
args = timing.add_arguments_and_parse(parser, timing.FILE(noquotes=True))
# Guard against being called with multiple processes
if MPI.COMM_WORLD.rank == 0:
# Make one big hexagon layout at the center of the focalplane.
# Compute the number of pixels that is at least the number requested.
test = args.minpix - 1
nrings = 0
while (test - 6 * nrings) > 0:
test -= 6 * nrings
nrings += 1
npix = 1
for r in range(1, nrings+1):
npix += 6 * r
print("using {} pixels ({} detectors)".format(npix, npix*2))
# Translate the field-of-view into distance between flag sides
angwidth = args.fov * np.cos(30 * degree)
Apol = tt.hex_pol_angles_qu(npix, offset=0.0)
Bpol = tt.hex_pol_angles_qu(npix, offset=90.0)
Adets = tt.hex_layout(npix, angwidth, "fake_", "A", Apol)
Bdets = tt.hex_layout(npix, angwidth, "fake_", "B", Bpol)
dets = Adets.copy()
dets.update(Bdets)
np.random.seed(args.random_seed)
for indx, d in enumerate(sorted(dets.keys())):
dets[d]["fknee"] = args.psd_fknee
dets[d]["fmin"] = args.psd_fmin
dets[d]["alpha"] = args.psd_alpha
dets[d]["NET"] = args.psd_NET
# This is in degrees, but the input is in arcmin.
dets[d]["fwhm_deg"] = (args.fwhm / 60.0) \
* (1 + np.random.randn()*args.fwhm_sigma)
# This is a fixed value, in arcmin.
dets[d]["fwhm"] = args.fwhm
if args.bandcenter_ghz:
dets[d]["bandcenter_ghz"] \
= args.bandcenter_ghz * (1+np.random.randn()*args.bandcenter_sigma)
if args.bandwidth_ghz:
dets[d]["bandwidth_ghz"] \
= args.bandwidth_ghz * (1+np.random.randn()*args.bandwidth_sigma)
dets[d]["index"] = indx
outfile = "{}_{}".format(args.out, npix)
qdets = { x : y["quat"] for x, y in dets.items() }
beams = { x : (60.0*y["fwhm_deg"]) for x, y in dets.items() }
tt.plot_focalplane(qdets, args.fov, args.fov, "{}.png".format(outfile),
fwhm=beams)
with open("{}.pkl".format(outfile), "wb") as p:
pickle.dump(dets, p)
return