_exposureSummaryStats.py

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# This file is part of afw.
#
# Developed for the LSST Data Management System.
# This product includes software developed by the LSST Project
# (https://www.lsst.org).
# See the COPYRIGHT file at the top-level directory of this distribution
# for details of code ownership.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.
from __future__ import annotations
 
import dataclasses
from typing import TYPE_CHECKING
import yaml
import warnings
 
from ..typehandling import Storable, StorableHelperFactory
 
if TYPE_CHECKING:
    from ..table import BaseRecord, Schema
 
__all__ = ("ExposureSummaryStats", )
 
 
def _default_corners():
    return [float("nan")] * 4
 
 
@dataclasses.dataclass
class ExposureSummaryStats(Storable):
    _persistence_name = 'ExposureSummaryStats'
 
    _factory = StorableHelperFactory(__name__, _persistence_name)
 
    version: int = 0
 
    psfSigma: float = float('nan')
    """PSF determinant radius (pixels)."""
 
    psfArea: float = float('nan')
    """PSF effective area (pixels**2)."""
 
    psfIxx: float = float('nan')
    """PSF shape Ixx (pixels**2)."""
 
    psfIyy: float = float('nan')
    """PSF shape Iyy (pixels**2)."""
 
    psfIxy: float = float('nan')
    """PSF shape Ixy (pixels**2)."""
 
    ra: float = float('nan')
    """Bounding box center Right Ascension (degrees)."""
 
    dec: float = float('nan')
    """Bounding box center Declination (degrees)."""
 
    pixelScale: float = float('nan')
    """Measured detector pixel scale (arcsec/pixel)."""
 
    zenithDistance: float = float('nan')
    """Bounding box center zenith distance (degrees)."""
 
    expTime: float = float('nan')
    """Exposure time of the exposure (seconds)."""
 
    zeroPoint: float = float('nan')
    """Mean zeropoint in detector (mag)."""
 
    skyBg: float = float('nan')
    """Average sky background (ADU)."""
 
    skyNoise: float = float('nan')
    """Average sky noise (ADU)."""
 
    meanVar: float = float('nan')
    """Mean variance of the weight plane (ADU**2)."""
 
    raCorners: list[float] = dataclasses.field(default_factory=_default_corners)
    """Right Ascension of bounding box corners (degrees)."""
 
    decCorners: list[float] = dataclasses.field(default_factory=_default_corners)
    """Declination of bounding box corners (degrees)."""
 
    astromOffsetMean: float = float('nan')
    """Astrometry match offset mean."""
 
    astromOffsetStd: float = float('nan')
    """Astrometry match offset stddev."""
 
    nPsfStar: int = 0
    """Number of stars used for psf model."""
 
    psfStarDeltaE1Median: float = float('nan')
    """Psf stars median E1 residual (starE1 - psfE1)."""
 
    psfStarDeltaE2Median: float = float('nan')
    """Psf stars median E2 residual (starE2 - psfE2)."""
 
    psfStarDeltaE1Scatter: float = float('nan')
    """Psf stars MAD E1 scatter (starE1 - psfE1)."""
 
    psfStarDeltaE2Scatter: float = float('nan')
    """Psf stars MAD E2 scatter (starE2 - psfE2)."""
 
    psfStarDeltaSizeMedian: float = float('nan')
    """Psf stars median size residual (starSize - psfSize)."""
 
    psfStarDeltaSizeScatter: float = float('nan')
    """Psf stars MAD size scatter (starSize - psfSize)."""
 
    psfStarScaledDeltaSizeScatter: float = float('nan')
    """Psf stars MAD size scatter scaled by psfSize**2."""
 
    psfTraceRadiusDelta: float = float('nan')
    """Delta (max - min) of the model psf trace radius values evaluated on a
    grid of unmasked pixels (pixels).
    """
 
    psfApFluxDelta: float = float('nan')
    """Delta (max - min) of the model psf aperture flux (with aperture radius of
    max(2, 3*psfSigma)) values evaluated on a grid of unmasked pixels.
    """
 
    psfApCorrSigmaScaledDelta: float = float('nan')
    """Delta (max - min) of the psf flux aperture correction factors scaled (divided)
    by the psfSigma evaluated on a grid of unmasked pixels.
    """
 
    maxDistToNearestPsf: float = float('nan')
    """Maximum distance of an unmasked pixel to its nearest model psf star
    (pixels).
    """
 
    effTime: float = float('nan')
    """Effective exposure time calculated from psfSigma, skyBg, and
    zeroPoint (seconds).
    """
 
    effTimePsfSigmaScale: float = float('nan')
    """PSF scaling of the effective exposure time."""
 
    effTimeSkyBgScale: float = float('nan')
    """Sky background scaling of the effective exposure time."""
 
    effTimeZeroPointScale: float = float('nan')
    """Zeropoint scaling of the effective exposure time."""
 
    magLim: float = float('nan')
    """Magnitude limit at fixed SNR (default SNR=5) calculated from psfSigma, skyBg,
    zeroPoint, and readNoise.
    """
 
    def __post_init__(self):
        Storable.__init__(self)
 
    def isPersistable(self):
        return True
 
    def _getPersistenceName(self):
        return self._persistence_name
 
    def _getPythonModule(self):
        return __name__
 
    def _write(self):
        return yaml.dump(dataclasses.asdict(self), encoding='utf-8')
 
    @staticmethod
    def _read(bytes):
        yamlDict = yaml.load(bytes, Loader=yaml.SafeLoader)
 
        # Special list of fields to forward to new names.
        forwardFieldDict = {"decl": "dec"}
 
        # For forwards compatibility, filter out any fields that are
        # not defined in the dataclass.
        droppedFields = []
        for _field in list(yamlDict.keys()):
            if _field not in ExposureSummaryStats.__dataclass_fields__:
                if _field in forwardFieldDict and forwardFieldDict[_field] not in yamlDict:
                    yamlDict[forwardFieldDict[_field]] = yamlDict[_field]
                else:
                    droppedFields.append(_field)
                yamlDict.pop(_field)
        if len(droppedFields) > 0:
            droppedFieldString = ", ".join([str(f) for f in droppedFields])
            plural = "s" if len(droppedFields) != 1 else ""
            them = "them" if len(droppedFields) > 1 else "it"
            warnings.warn(
                f"Summary field{plural} [{droppedFieldString}] not recognized by this software version;"
                f" ignoring {them}.",
                FutureWarning,
                stacklevel=2,
            )
        return ExposureSummaryStats(**yamlDict)
 
    @classmethod
    def update_schema(cls, schema: Schema) -> None:
        """Update an schema to includes for all summary statistic fields.
 
        Parameters
        -------
        schema : `lsst.afw.table.Schema`
            Schema to add which fields will be added.
        """
        schema.addField(
            "psfSigma",
            type="F",
            doc="PSF model second-moments determinant radius (center of chip) (pixel)",
            units="pixel",
        )
        schema.addField(
            "psfArea",
            type="F",
            doc="PSF model effective area (center of chip) (pixel**2)",
            units='pixel**2',
        )
        schema.addField(
            "psfIxx",
            type="F",
            doc="PSF model Ixx (center of chip) (pixel**2)",
            units='pixel**2',
        )
        schema.addField(
            "psfIyy",
            type="F",
            doc="PSF model Iyy (center of chip) (pixel**2)",
            units='pixel**2',
        )
        schema.addField(
            "psfIxy",
            type="F",
            doc="PSF model Ixy (center of chip) (pixel**2)",
            units='pixel**2',
        )
        schema.addField(
            "raCorners",
            type="ArrayD",
            size=4,
            doc="Right Ascension of bounding box corners (degrees)",
            units="degree",
        )
        schema.addField(
            "decCorners",
            type="ArrayD",
            size=4,
            doc="Declination of bounding box corners (degrees)",
            units="degree",
        )
        schema.addField(
            "ra",
            type="D",
            doc="Right Ascension of bounding box center (degrees)",
            units="degree",
        )
        schema.addField(
            "dec",
            type="D",
            doc="Declination of bounding box center (degrees)",
            units="degree",
        )
        schema.addField(
            "zenithDistance",
            type="F",
            doc="Zenith distance of bounding box center (degrees)",
            units="degree",
        )
        schema.addField(
            "pixelScale",
            type="F",
            doc="Measured detector pixel scale (arcsec/pixel)",
            units="arcsec/pixel",
        )
        schema.addField(
            "expTime",
            type="F",
            doc="Exposure time of the exposure (seconds)",
            units="second",
        )
        schema.addField(
            "zeroPoint",
            type="F",
            doc="Mean zeropoint in detector (mag)",
            units="mag",
        )
        schema.addField(
            "skyBg",
            type="F",
            doc="Average sky background (ADU)",
            units="adu",
        )
        schema.addField(
            "skyNoise",
            type="F",
            doc="Average sky noise (ADU)",
            units="adu",
        )
        schema.addField(
            "meanVar",
            type="F",
            doc="Mean variance of the weight plane (ADU**2)",
            units="adu**2"
        )
        schema.addField(
            "astromOffsetMean",
            type="F",
            doc="Mean offset of astrometric calibration matches (arcsec)",
            units="arcsec",
        )
        schema.addField(
            "astromOffsetStd",
            type="F",
            doc="Standard deviation of offsets of astrometric calibration matches (arcsec)",
            units="arcsec",
        )
        schema.addField("nPsfStar", type="I", doc="Number of stars used for PSF model")
        schema.addField(
            "psfStarDeltaE1Median",
            type="F",
            doc="Median E1 residual (starE1 - psfE1) for psf stars",
        )
        schema.addField(
            "psfStarDeltaE2Median",
            type="F",
            doc="Median E2 residual (starE2 - psfE2) for psf stars",
        )
        schema.addField(
            "psfStarDeltaE1Scatter",
            type="F",
            doc="Scatter (via MAD) of E1 residual (starE1 - psfE1) for psf stars",
        )
        schema.addField(
            "psfStarDeltaE2Scatter",
            type="F",
            doc="Scatter (via MAD) of E2 residual (starE2 - psfE2) for psf stars",
        )
        schema.addField(
            "psfStarDeltaSizeMedian",
            type="F",
            doc="Median size residual (starSize - psfSize) for psf stars (pixel)",
            units="pixel",
        )
        schema.addField(
            "psfStarDeltaSizeScatter",
            type="F",
            doc="Scatter (via MAD) of size residual (starSize - psfSize) for psf stars (pixel)",
            units="pixel",
        )
        schema.addField(
            "psfStarScaledDeltaSizeScatter",
            type="F",
            doc="Scatter (via MAD) of size residual scaled by median size squared",
        )
        schema.addField(
            "psfTraceRadiusDelta",
            type="F",
            doc="Delta (max - min) of the model psf trace radius values evaluated on a grid of "
            "unmasked pixels (pixel).",
            units="pixel",
        )
        schema.addField(
            "psfApFluxDelta",
            type="F",
            doc="Delta (max - min) of the model psf aperture flux (with aperture radius of "
            "max(2, 3*psfSigma)) values evaluated on a grid of unmasked pixels.",
        )
        schema.addField(
            "psfApCorrSigmaScaledDelta",
            type="F",
            doc="Delta (max - min) of the model psf aperture correction factors scaled (divided) "
            "by the psfSigma evaluated on a grid of unmasked pixels.",
        )
        schema.addField(
            "maxDistToNearestPsf",
            type="F",
            doc="Maximum distance of an unmasked pixel to its nearest model psf star (pixel).",
            units="pixel",
        )
        schema.addField(
            "effTime",
            type="F",
            doc="Effective exposure time calculated from psfSigma, skyBg, and "
            "zeroPoint (seconds).",
            units="second",
        )
        schema.addField(
            "effTimePsfSigmaScale",
            type="F",
            doc="PSF scaling of the effective exposure time."
        )
        schema.addField(
            "effTimeSkyBgScale",
            type="F",
            doc="Sky background scaling of the effective exposure time."
        )
        schema.addField(
            "effTimeZeroPointScale",
            type="F",
            doc="Zeropoint scaling of the effective exposure time."
        )
        schema.addField(
            "magLim",
            type="F",
            doc="Magnitude limit at SNR=5 (M5) calculated from psfSigma, "
            "skyBg, zeroPoint, and readNoise.",
            units="mag",
        )
 
    def update_record(self, record: BaseRecord) -> None:
        """Write summary-statistic columns into a record.
 
        Parameters
        ----------
        record : `lsst.afw.table.BaseRecord`
            Record to update.  This is expected to frequently be an
            `ExposureRecord` instance (with higher-level code adding other
            columns and objects), but this method can work with any record
            type.
        """
        for field in dataclasses.fields(self):
            value = getattr(self, field.name)
            if field.name == "version":
                continue
            elif field.type.startswith("list"):
                record[field.name][:] = value
            else:
                record[field.name] = value
 
    @classmethod
    def from_record(cls, record: BaseRecord) -> ExposureSummaryStats:
        """Read summary-statistic columns from a record into ``self``.
 
        Parameters
        ----------
        record : `lsst.afw.table.BaseRecord`
            Record to read from.  This is expected to frequently be an
            `ExposureRecord` instance (with higher-level code adding other
            columns and objects), but this method can work with any record
            type, ignoring any attributes or columns it doesn't recognize.
 
        Returns
        -------
        summary : `ExposureSummaryStats`
            Summary statistics object created from the given record.
        """
        return cls(
            **{
                field.name: (
                    record[field.name] if not field.type.startswith("list")
                    else [float(v) for v in record[field.name]]
                )
                for field in dataclasses.fields(cls)
                if field.name != "version"
            }
        )