Source code for galsim.config.photon_ops

# Copyright (c) 2012-2023 by the GalSim developers team on GitHub
# https://github.com/GalSim-developers
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# This file is part of GalSim: The modular galaxy image simulation toolkit.
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import logging

from .util import LoggerWrapper, GetIndex, GetRNG, get_cls_params
from .value import ParseValue, GetAllParams, CheckAllParams, SetDefaultIndex
from .input import RegisterInputConnectedType
from .sed import BuildSED
from ..errors import GalSimConfigError, GalSimConfigValueError
from ..utilities import basestring
from ..photon_array import PhotonArray, PhotonOp
from ..photon_array import WavelengthSampler, FRatioAngles, PhotonDCR, Refraction, FocusDepth
from ..photon_array import TimeSampler, PupilImageSampler, PupilAnnulusSampler

# This file handles the construction of photon_ops in config['stamp']['photon_ops'].

# This module-level dict will store all the registered photon_op types.
# See the RegisterPhotonOpType function at the end of this file.
# The keys are the (string) names of the photon_ops types, and the values will be builders that
# know how to build the photon operator object.
valid_photon_op_types = {}


def BuildPhotonOps(config, key, base, logger=None):
    """Read the parameters from config[key] (which should be a list) and return a constructed
    photon_ops as a list.

    Parameters:
        config:     A dict with the configuration information for the photon ops.
                    (usually base['stamp'])
        key:        The key in the dict for the photon_ops list.
        base:       The base dict of the configuration.
        logger:     Optionally, provide a logger for logging debug statements. [default: None]

    Returns:
        the photon_ops list
    """
    logger = LoggerWrapper(logger)
    if not isinstance(config[key], list):
        raise GalSimConfigError("photon_ops must be a list")
    photon_ops = config[key]  # The list in the config dict
    ops = [] # List of the actual operators
    for i in range(len(photon_ops)):
        op = BuildPhotonOp(photon_ops, i, base, logger)
        ops.append(op)
    return ops

def BuildPhotonOp(config, key, base, logger=None):
    """Read the parameters from config[key] and return a single constructed photon_op object.

    Parameters:
        config:     A list with the configuration information for the photon ops.
                    (usually base['stamp']['photon_ops'])
        key:        The index in the list for this photon_op.  It's called key, since for most
                    things, this is a key into a dict, but here it's normally an integer index
                    into the photon_ops list.
        base:       The base dict of the configuration.
        logger:     Optionally, provide a logger for logging debug statements. [default: None]

    Returns:
        a object that would be valid in a photon_ops list
    """
    logger = LoggerWrapper(logger)
    logger.debug('obj %d: Start BuildPhotonOp key = %s',base.get('obj_num',0),key)

    param = config[key]

    # Check for direct value, else get the type
    if isinstance(param, PhotonOp):
        return param
    elif isinstance(param, basestring) and (param[0] == '$' or param[0] == '@'):
        return ParseValue(config, key, base, None)[0]
    elif isinstance(param, dict) and 'type' in param:
        op_type = param['type']
    else:
        raise GalSimConfigError("photon_op must be either a PhotonOp or a dict")

    # For these two, just do the usual ParseValue function.
    if op_type in ('Eval', 'Current'):
        return ParseValue(config, key, base, None)[0]

    if op_type not in valid_photon_op_types:
        raise GalSimConfigValueError("Invalid photon_op type.", op_type,
                                     list(valid_photon_op_types.keys()))

    # Check if we can use the current cached object
    index, index_key = GetIndex(param, base)
    if 'current' in param:
        cop, csafe, cvalue_type, cindex, cindex_key = param['current']
        if cindex == index:
            logger.debug('obj %d: The photon_op is already current', base.get('obj_num',0))
            logger.debug('obj %d: index_key = %s, index = %d',base.get('obj_num',0),
                         cindex_key, cindex)
            return cop

    # Need to use a builder.
    logger.debug('obj %d: Building photon_op type %s', base.get('obj_num',0), op_type)
    builder = valid_photon_op_types[op_type]
    op = builder.buildPhotonOp(param, base, logger)
    logger.debug('obj %d: photon_op = %s', base.get('obj_num',0), str(op))

    param['current'] = op, False, None, index, index_key

    return op


[docs]class PhotonOpBuilder: """A base class for building PhotonOp objects. The base class defines the call signatures of the methods that any derived class should follow. """
[docs] def buildPhotonOp(self, config, base, logger): """Build the PhotonOp based on the specifications in the config dict. Note: Sub-classes must override this function with a real implementation. Parameters: config: The configuration dict for the PhotonOp base: The base configuration dict. logger: If provided, a logger for logging debug statements. Returns: the constructed PhotonOp object. """ raise NotImplementedError("The %s class has not overridden buildPhotonOp"%self.__class__)
class SimplePhotonOpBuilder(PhotonOpBuilder): """A class for building simple PhotonOp objects. The initializer takes an init_func, which is the class or function to call to build the PhotonOp. For the kwargs, it calls getKwargs, which does the normal parsing of the req_params and related class attributes. """ def __init__(self, init_func): self.init_func = init_func def getKwargs(self, config, base, logger): """Get the kwargs to pass to the build function based on the following attributes of init_func: _req_params A dict of required parameters and their types. _opt_params A dict of optional parameters and their types. _single_params A list of dicts of parameters such that one and only one of parameter in each dict is required. _takes_rng A bool value saying whether an rng object is required. See the classes in photon_array.py for examples of classes that set these attributes. Parameters: config: The configuration dict for the photon_op type. base: The base configuration dict. logger: If provided, a logger for logging debug statements. Returns: kwargs """ req, opt, single, takes_rng = get_cls_params(self.init_func) kwargs, safe = GetAllParams(config, base, req, opt, single) if takes_rng: # pragma: no cover None of ours have this anymore. But it's still allowed. kwargs['rng'] = GetRNG(config, base, logger, self.init_func.__name__) return kwargs def buildPhotonOp(self, config, base, logger): """Build the PhotonOp based on the specifications in the config dict. Parameters: config: The configuration dict for the photon_op type. base: The base configuration dict. logger: If provided, a logger for logging debug statements. Returns: the constructed PhotonOp object. """ kwargs = self.getKwargs(config,base,logger) return self.init_func(**kwargs) class WavelengthSamplerBuilder(PhotonOpBuilder): """Build a WavelengthSampler """ # This one needs special handling for sed and bandpass def buildPhotonOp(self, config, base, logger): req, opt, single, takes_rng = get_cls_params(WavelengthSampler) kwargs, safe = GetAllParams(config, base, req, opt, single, ignore=['sed']) if 'sed' not in config: raise GalSimConfigError("sed is required for WavelengthSampler") sed = BuildSED(config, 'sed', base, logger)[0] kwargs['sed'] = sed if 'bandpass' not in base: raise GalSimConfigError("bandpass is required for WavelengthSampler") kwargs['bandpass'] = base['bandpass'] return WavelengthSampler(**kwargs) class PhotonDCRBuilder(PhotonOpBuilder): """Build a PhotonDCR """ # This one needs special handling for obj_coord def buildPhotonOp(self, config, base, logger): req, opt, single, takes_rng = get_cls_params(PhotonDCR) kwargs, safe = GetAllParams(config, base, req, opt, single) if 'sky_pos' in base: kwargs['obj_coord'] = base['sky_pos'] return PhotonDCR(**kwargs) class ListPhotonOpBuilder(PhotonOpBuilder): """Select a photon_op from a list """ def buildPhotonOp(self, config, base, logger): req = { 'items' : list } opt = { 'index' : int } # Only Check, not Get. We need to handle items a bit differently, since it's a list. CheckAllParams(config, req=req, opt=opt) items = config['items'] if not isinstance(items,list): raise GalSimConfigError("items entry for type=List is not a list.") # Setup the indexing sequence if it hasn't been specified using the length of items. SetDefaultIndex(config, len(items)) index, safe = ParseValue(config, 'index', base, int) if index < 0 or index >= len(items): raise GalSimConfigError("index %d out of bounds for photon_op type=List"%index) return BuildPhotonOp(items, index, base)
[docs]def RegisterPhotonOpType(photon_op_type, builder, input_type=None): """Register a photon_op type for use by the config apparatus. Parameters: photon_op_type: The name of the config type to register builder: A builder object to use for building the PhotonOp object. It should be an instance of a subclass of PhotonOpBuilder. input_type: If the PhotonOp builder utilises an input object, give the key name of the input type here. (If it uses more than one, this may be a list.) [default: None] """ valid_photon_op_types[photon_op_type] = builder RegisterInputConnectedType(input_type, photon_op_type)
RegisterPhotonOpType('WavelengthSampler', WavelengthSamplerBuilder()) RegisterPhotonOpType('FRatioAngles', SimplePhotonOpBuilder(FRatioAngles)) RegisterPhotonOpType('PhotonDCR', PhotonDCRBuilder()) RegisterPhotonOpType('Refraction', SimplePhotonOpBuilder(Refraction)) RegisterPhotonOpType('FocusDepth', SimplePhotonOpBuilder(FocusDepth)) RegisterPhotonOpType('List', ListPhotonOpBuilder()) RegisterPhotonOpType('PupilImageSampler', SimplePhotonOpBuilder(PupilImageSampler)) RegisterPhotonOpType('PupilAnnulusSampler', SimplePhotonOpBuilder(PupilAnnulusSampler)) RegisterPhotonOpType('TimeSampler', SimplePhotonOpBuilder(TimeSampler))