MapSim¶
- class mapsims.MapSim(channels, nside=None, modeling_nside=None, lmax_over_nside=None, car=False, healpix=True, car_resolution=None, num=0, nsplits=1, unit='uK_CMB', output_folder='output', tag='sky', output_filename_template='mapsims_{tag}_{telescope}_{band}_nside{nside}_{split}_of_{nsplits}_{pixelization}.fits', pysm_components_string=None, output_reference_frame=None, pysm_custom_components=None, other_components=None, instrument_parameters=None)[source] [edit on github]¶
Bases:
object
Run map based simulations
MapSim executes PySM for each of the input channels with a sky defined by default PySM components in
pysm_components_string
and custom components inpysm_custom_components
and rotates in Alm space to the reference frameoutput_reference_frame
. Then for each of the channels specified, smoothes the map with the channel beam and finally adds the map generated byother_components
, for example noise maps, and writes the outputs to disk.- Parameters:
- channelsstr
If “all”, all channels are included. Otherwise a list of channel tags: LT1_UHF1 and LT0_UHF1 = “LT1_UHF1,LT0_UHF1” Otherwise, provide a string with: * a key, e.g. tube or telescope * : * comma separated list of desider values e.g. all SAT channels = “telescope:SA” LT1 and LT2 tubes = “tube:LT1,LT2”
- modeling_nsideint
Run PySM at higher Nside to increase the accuracy of the results, it is recommended to set modeling Nside twice of nside If None, modeling is done using
nside
- nsideint
output HEALPix Nside, if None, automatically pick the default resolution of the first channel, see https://github.com/simonsobs/mapsims/tree/master/mapsims/data/so_default_resolution.csv
- lmax_over_nsidefloat
used to compute Ell_max used in the smoothing process
- carbool
True for CAR output
- healpixbool
True for HEALPix output
- car_resolutionastropy.Quantity
CAR pixels resolution with angle unit
- unitstr
Unit of output maps
- output_folderstr
Relative or absolute path to output folder, string template with {nside} and {tag} fields
- numint
Realization number, generally used as seed, default is 0, automatically padded to 4 digits
- nsplitsint
Number of noise splits, see the documentation of
SONoiseSimulator
- tagstr
String to describe the current simulation, for example its content, which is used into string interpolation for
output_folder
andoutput_filename_template
- output_filename_templatestr
String template with {telescope} {channel} {nside} {tag} fields
- pysm_components_stringstr
Comma separated string of PySM components, i.e. “s1,d4,a2”
- output_reference_framestr
The requested output reference frame G for Galactic, C for Equatorial or E for Ecliptic, set to None to apply no rotation
- pysm_custom_componentsdict
Dictionary of other components executed through PySM
- other_componentsdict
Dictionary of component name, component class pairs, the output of these are not rotated, they should already be in the same reference frame specified in output_reference_frame.
- instrument_parametersascii file in IPAC table format path or str
A string specifies an instrument parameters file included in the package
data/
folder A path or a string containing a path to an externally provided IPAC table file with the expected format. Instrument parameters in IPAC ascii format, one channel per row, with columns (with units):tag, band, center_frequency, fwhm
It also assumes that in the same folder there are IPAC table files named bandpass_{tag}.tbl with columns:
bandpass_frequency, bandpass_weight
Methods Summary
execute
([write_outputs])Run map simulations
Methods Documentation
- execute(write_outputs=False)[source] [edit on github]¶
Run map simulations
Execute simulations for all channels and write to disk the maps, and return their filenames (relative to output folder) unless
write_outputs
is False, then return them.