Coverage for python/lsst/meas/algorithms/loadReferenceObjects.py: 13%
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« prev ^ index » next coverage.py v6.4.4, created at 2022-08-20 02:04 -0700
1#
2# LSST Data Management System
3#
4# Copyright 2008-2017 AURA/LSST.
5#
6# This product includes software developed by the
7# LSST Project (http://www.lsst.org/).
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14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
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18#
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21# see <https://www.lsstcorp.org/LegalNotices/>.
22#
24__all__ = ["getRefFluxField", "getRefFluxKeys", "LoadReferenceObjectsTask", "LoadReferenceObjectsConfig",
25 "ReferenceObjectLoader", "ReferenceObjectLoaderBase"]
27import abc
28import logging
29import warnings
30from deprecated.sphinx import deprecated
32import astropy.time
33import astropy.units
34import numpy
36import lsst.geom as geom
37import lsst.afw.table as afwTable
38import lsst.pex.config as pexConfig
39import lsst.pipe.base as pipeBase
40from lsst import sphgeom
41from lsst.daf.base import PropertyList
44# TODO DM-34793: remove this function
45def isOldFluxField(name, units):
46 """Return True if this name/units combination corresponds to an
47 "old-style" reference catalog flux field.
48 """
49 unitsCheck = units != 'nJy' # (units == 'Jy' or units == '' or units == '?')
50 isFlux = name.endswith('_flux')
51 isFluxSigma = name.endswith('_fluxSigma')
52 isFluxErr = name.endswith('_fluxErr')
53 return (isFlux or isFluxSigma or isFluxErr) and unitsCheck
56# TODO DM-34793: remove this function
57def hasNanojanskyFluxUnits(schema):
58 """Return True if the units of all flux and fluxErr are correct (nJy).
59 """
60 for field in schema:
61 if isOldFluxField(field.field.getName(), field.field.getUnits()):
62 return False
63 return True
66def getFormatVersionFromRefCat(refCat):
67 """"Return the format version stored in a reference catalog header.
69 Parameters
70 ----------
71 refCat : `lsst.afw.table.SimpleCatalog`
72 Reference catalog to inspect.
74 Returns
75 -------
76 version : `int`
77 Format verison integer. Returns `0` if the catalog has no metadata
78 or the metadata does not include a "REFCAT_FORMAT_VERSION" key.
79 """
80 # TODO DM-34793: change to "Version 0 refcats are no longer supported: refcat fluxes must have nJy units."
81 # TODO DM-34793: and raise an exception instead of returning 0.
82 deprecation_msg = "Support for version 0 refcats (pre-nJy fluxes) will be removed after v25."
83 md = refCat.getMetadata()
84 if md is None:
85 warnings.warn(deprecation_msg)
86 return 0
87 try:
88 return md.getScalar("REFCAT_FORMAT_VERSION")
89 except KeyError:
90 warnings.warn(deprecation_msg)
91 return 0
94# TODO DM-34793: remove this function
95@deprecated(reason="Support for version 0 refcats (pre-nJy fluxes) will be removed after v25.",
96 version="v24.0", category=FutureWarning)
97def convertToNanojansky(catalog, log, doConvert=True):
98 """Convert fluxes in a catalog from jansky to nanojansky.
100 Parameters
101 ----------
102 catalog : `lsst.afw.table.SimpleCatalog`
103 The catalog to convert.
104 log : `lsst.log.Log` or `logging.Logger`
105 Log to send messages to.
106 doConvert : `bool`, optional
107 Return a converted catalog, or just identify the fields that need to be converted?
108 This supports the "write=False" mode of `bin/convert_to_nJy.py`.
110 Returns
111 -------
112 catalog : `lsst.afw.table.SimpleCatalog` or None
113 The converted catalog, or None if ``doConvert`` is False.
115 Notes
116 -----
117 Support for old units in reference catalogs will be removed after the
118 release of late calendar year 2019.
119 Use `meas_algorithms/bin/convert_to_nJy.py` to update your reference catalog.
120 """
121 # Do not share the AliasMap: for refcats, that gets created when the
122 # catalog is read from disk and should not be propagated.
123 mapper = afwTable.SchemaMapper(catalog.schema, shareAliasMap=False)
124 mapper.addMinimalSchema(afwTable.SimpleTable.makeMinimalSchema())
125 input_fields = []
126 output_fields = []
127 for field in catalog.schema:
128 oldName = field.field.getName()
129 oldUnits = field.field.getUnits()
130 if isOldFluxField(oldName, oldUnits):
131 units = 'nJy'
132 # remap Sigma flux fields to Err, so we can drop the alias
133 if oldName.endswith('_fluxSigma'):
134 name = oldName.replace('_fluxSigma', '_fluxErr')
135 else:
136 name = oldName
137 newField = afwTable.Field[field.dtype](name, field.field.getDoc(), units)
138 mapper.addMapping(field.getKey(), newField)
139 input_fields.append(field.field)
140 output_fields.append(newField)
141 else:
142 mapper.addMapping(field.getKey())
144 fluxFieldsStr = '; '.join("(%s, '%s')" % (field.getName(), field.getUnits()) for field in input_fields)
146 if doConvert:
147 newSchema = mapper.getOutputSchema()
148 output = afwTable.SimpleCatalog(newSchema)
149 output.reserve(len(catalog))
150 output.extend(catalog, mapper=mapper)
151 for field in output_fields:
152 output[field.getName()] *= 1e9
153 log.info("Converted refcat flux fields to nJy (name, units): %s", fluxFieldsStr)
154 return output
155 else:
156 log.info("Found old-style refcat flux fields (name, units): %s", fluxFieldsStr)
157 return None
160class _FilterCatalog:
161 """This is a private helper class which filters catalogs by
162 row based on the row being inside the region used to initialize
163 the class.
165 Parameters
166 ----------
167 region : `lsst.sphgeom.Region`
168 The spatial region which all objects should lie within
169 """
170 def __init__(self, region):
171 self.region = region
173 def __call__(self, refCat, catRegion):
174 """This call method on an instance of this class takes in a reference
175 catalog, and the region from which the catalog was generated.
177 If the catalog region is entirely contained within the region used to
178 initialize this class, then all the entries in the catalog must be
179 within the region and so the whole catalog is returned.
181 If the catalog region is not entirely contained, then the location for
182 each record is tested against the region used to initialize the class.
183 Records which fall inside this region are added to a new catalog, and
184 this catalog is then returned.
186 Parameters
187 ---------
188 refCat : `lsst.afw.table.SourceCatalog`
189 SourceCatalog to be filtered.
190 catRegion : `lsst.sphgeom.Region`
191 Region in which the catalog was created
192 """
193 if catRegion.isWithin(self.region):
194 # no filtering needed, region completely contains refcat
195 return refCat
197 filteredRefCat = type(refCat)(refCat.table)
198 for record in refCat:
199 if self.region.contains(record.getCoord().getVector()):
200 filteredRefCat.append(record)
201 return filteredRefCat
204class LoadReferenceObjectsConfig(pexConfig.Config):
205 pixelMargin = pexConfig.RangeField(
206 doc="Padding to add to 4 all edges of the bounding box (pixels)",
207 dtype=int,
208 default=250,
209 min=0,
210 )
211 anyFilterMapsToThis = pexConfig.Field(
212 doc=("Always use this reference catalog filter, no matter whether or what filter name is "
213 "supplied to the loader. Effectively a trivial filterMap: map all filter names to this filter."
214 " This can be set for purely-astrometric catalogs (e.g. Gaia DR2) where there is only one "
215 "reasonable choice for every camera filter->refcat mapping, but not for refcats used for "
216 "photometry, which need a filterMap and/or colorterms/transmission corrections."),
217 dtype=str,
218 default=None,
219 optional=True
220 )
221 filterMap = pexConfig.DictField(
222 doc=("Mapping of camera filter name: reference catalog filter name; "
223 "each reference filter must exist in the refcat."
224 " Note that this does not perform any bandpass corrections: it is just a lookup."),
225 keytype=str,
226 itemtype=str,
227 default={},
228 )
229 requireProperMotion = pexConfig.Field(
230 doc="Require that the fields needed to correct proper motion "
231 "(epoch, pm_ra and pm_dec) are present?",
232 dtype=bool,
233 default=False,
234 )
235 ref_dataset_name = pexConfig.Field(
236 doc="Deprecated; do not use. Added for easier transition from LoadIndexedReferenceObjectsConfig to "
237 "LoadReferenceObjectsConfig",
238 dtype=str,
239 default='',
240 deprecated='This field is not used. It will be removed after v25.',
241 )
243 def validate(self):
244 super().validate()
245 if self.filterMap != {} and self.anyFilterMapsToThis is not None:
246 msg = "`filterMap` and `anyFilterMapsToThis` are mutually exclusive"
247 raise pexConfig.FieldValidationError(LoadReferenceObjectsConfig.anyFilterMapsToThis,
248 self, msg)
251class ReferenceObjectLoader:
252 """This class facilitates loading reference catalogs.
254 The QuantumGraph generation will create a list of datasets that may
255 possibly overlap a given region. These datasets are then used to construct
256 an instance of this class. The class instance should then be passed into
257 a task which needs reference catalogs. These tasks should then determine
258 the exact region of the sky reference catalogs will be loaded for, and
259 call a corresponding method to load the reference objects.
261 Parameters
262 ----------
263 dataIds : iterable of `lsst.daf.butler.DataCoordinate`
264 An iterable object of data IDs that point to reference catalogs.
265 refCats : iterable of `lsst.daf.butler.DeferredDatasetHandle`
266 Handles to load refCats on demand.
267 log : `lsst.log.Log`, `logging.Logger` or `None`, optional
268 Logger object used to write out messages. If `None` a default
269 logger will be used.
270 """
271 ConfigClass = LoadReferenceObjectsConfig
273 def __init__(self, dataIds, refCats, log=None, config=None, **kwargs):
274 if kwargs:
275 warnings.warn("Instantiating ReferenceObjectLoader with additional kwargs is deprecated "
276 "and will be removed after v25.0", FutureWarning, stacklevel=2)
278 if config is None:
279 config = self.ConfigClass()
280 self.config = config
281 self.dataIds = dataIds
282 self.refCats = refCats
283 self.log = log or logging.getLogger(__name__).getChild("ReferenceObjectLoader")
285 def applyProperMotions(self, catalog, epoch):
286 """Apply proper motion correction to a reference catalog.
288 Adjust position and position error in the ``catalog``
289 for proper motion to the specified ``epoch``,
290 modifying the catalog in place.
292 Parameters
293 ----------
294 catalog : `lsst.afw.table.SimpleCatalog`
295 Catalog of positions, containing at least these fields:
297 - Coordinates, retrieved by the table's coordinate key.
298 - ``coord_raErr`` : Error in Right Ascension (rad).
299 - ``coord_decErr`` : Error in Declination (rad).
300 - ``pm_ra`` : Proper motion in Right Ascension (rad/yr,
301 East positive)
302 - ``pm_raErr`` : Error in ``pm_ra`` (rad/yr), optional.
303 - ``pm_dec`` : Proper motion in Declination (rad/yr,
304 North positive)
305 - ``pm_decErr`` : Error in ``pm_dec`` (rad/yr), optional.
306 - ``epoch`` : Mean epoch of object (an astropy.time.Time)
307 epoch : `astropy.time.Time`
308 Epoch to which to correct proper motion.
309 If None, do not apply PM corrections or raise if
310 ``config.requireProperMotion`` is True.
312 Raises
313 ------
314 RuntimeError
315 Raised if ``config.requireProperMotion`` is set but we cannot
316 apply the proper motion correction for some reason.
317 """
318 if epoch is None:
319 if self.config.requireProperMotion:
320 raise RuntimeError("requireProperMotion=True but epoch not provided to loader.")
321 else:
322 self.log.debug("No epoch provided: not applying proper motion corrections to refcat.")
323 return
325 # Warn/raise for a catalog in an incorrect format, if epoch was specified.
326 if ("pm_ra" in catalog.schema
327 and not isinstance(catalog.schema["pm_ra"].asKey(), afwTable.KeyAngle)):
328 if self.config.requireProperMotion:
329 raise RuntimeError("requireProperMotion=True but refcat pm_ra field is not an Angle.")
330 else:
331 self.log.warning("Reference catalog pm_ra field is not an Angle; cannot apply proper motion.")
332 return
334 if ("epoch" not in catalog.schema or "pm_ra" not in catalog.schema):
335 if self.config.requireProperMotion:
336 raise RuntimeError("requireProperMotion=True but PM data not available from catalog.")
337 else:
338 self.log.warning("Proper motion correction not available for this reference catalog.")
339 return
341 applyProperMotionsImpl(self.log, catalog, epoch)
343 @staticmethod
344 def makeMinimalSchema(filterNameList, *, addCentroid=False,
345 addIsPhotometric=False, addIsResolved=False,
346 addIsVariable=False, coordErrDim=2,
347 addProperMotion=False, properMotionErrDim=2,
348 addParallax=False):
349 """Make a standard schema for reference object catalogs.
351 Parameters
352 ----------
353 filterNameList : `list` of `str`
354 List of filter names. Used to create <filterName>_flux fields.
355 addIsPhotometric : `bool`
356 If True then add field "photometric".
357 addIsResolved : `bool`
358 If True then add field "resolved".
359 addIsVariable : `bool`
360 If True then add field "variable".
361 coordErrDim : `int`
362 Number of coord error fields; must be one of 0, 2, 3:
364 - If 2 or 3: add fields "coord_raErr" and "coord_decErr".
365 - If 3: also add field "coord_radecErr".
366 addProperMotion : `bool`
367 If True add fields "epoch", "pm_ra", "pm_dec" and "pm_flag".
368 properMotionErrDim : `int`
369 Number of proper motion error fields; must be one of 0, 2, 3;
370 ignored if addProperMotion false:
371 - If 2 or 3: add fields "pm_raErr" and "pm_decErr".
372 - If 3: also add field "pm_radecErr".
373 addParallax : `bool`
374 If True add fields "epoch", "parallax", "parallaxErr"
375 and "parallax_flag".
377 Returns
378 -------
379 schema : `lsst.afw.table.Schema`
380 Schema for reference catalog, an
381 `lsst.afw.table.SimpleCatalog`.
383 Notes
384 -----
385 Reference catalogs support additional covariances, such as
386 covariance between RA and proper motion in declination,
387 that are not supported by this method, but can be added after
388 calling this method.
389 """
390 schema = afwTable.SimpleTable.makeMinimalSchema()
391 if addCentroid:
392 afwTable.Point2DKey.addFields(
393 schema,
394 "centroid",
395 "centroid on an exposure, if relevant",
396 "pixel",
397 )
398 schema.addField(
399 field="hasCentroid",
400 type="Flag",
401 doc="is position known?",
402 )
403 for filterName in filterNameList:
404 schema.addField(
405 field="%s_flux" % (filterName,),
406 type=numpy.float64,
407 doc="flux in filter %s" % (filterName,),
408 units="nJy",
409 )
410 for filterName in filterNameList:
411 schema.addField(
412 field="%s_fluxErr" % (filterName,),
413 type=numpy.float64,
414 doc="flux uncertainty in filter %s" % (filterName,),
415 units="nJy",
416 )
417 if addIsPhotometric:
418 schema.addField(
419 field="photometric",
420 type="Flag",
421 doc="set if the object can be used for photometric calibration",
422 )
423 if addIsResolved:
424 schema.addField(
425 field="resolved",
426 type="Flag",
427 doc="set if the object is spatially resolved",
428 )
429 if addIsVariable:
430 schema.addField(
431 field="variable",
432 type="Flag",
433 doc="set if the object has variable brightness",
434 )
435 if coordErrDim not in (0, 2, 3):
436 raise ValueError("coordErrDim={}; must be (0, 2, 3)".format(coordErrDim))
437 if coordErrDim > 0:
438 afwTable.CovarianceMatrix2fKey.addFields(
439 schema=schema,
440 prefix="coord",
441 names=["ra", "dec"],
442 units=["rad", "rad"],
443 diagonalOnly=(coordErrDim == 2),
444 )
446 if addProperMotion or addParallax:
447 schema.addField(
448 field="epoch",
449 type=numpy.float64,
450 doc="date of observation (TAI, MJD)",
451 units="day",
452 )
454 if addProperMotion:
455 schema.addField(
456 field="pm_ra",
457 type="Angle",
458 doc="proper motion in the right ascension direction = dra/dt * cos(dec)",
459 units="rad/year",
460 )
461 schema.addField(
462 field="pm_dec",
463 type="Angle",
464 doc="proper motion in the declination direction",
465 units="rad/year",
466 )
467 if properMotionErrDim not in (0, 2, 3):
468 raise ValueError("properMotionErrDim={}; must be (0, 2, 3)".format(properMotionErrDim))
469 if properMotionErrDim > 0:
470 afwTable.CovarianceMatrix2fKey.addFields(
471 schema=schema,
472 prefix="pm",
473 names=["ra", "dec"],
474 units=["rad/year", "rad/year"],
475 diagonalOnly=(properMotionErrDim == 2),
476 )
477 schema.addField(
478 field="pm_flag",
479 type="Flag",
480 doc="Set if proper motion or proper motion error is bad",
481 )
483 if addParallax:
484 schema.addField(
485 field="parallax",
486 type="Angle",
487 doc="parallax",
488 units="rad",
489 )
490 schema.addField(
491 field="parallaxErr",
492 type="Angle",
493 doc="uncertainty in parallax",
494 units="rad",
495 )
496 schema.addField(
497 field="parallax_flag",
498 type="Flag",
499 doc="Set if parallax or parallax error is bad",
500 )
501 return schema
503 @staticmethod
504 def _remapReferenceCatalogSchema(refCat, *, anyFilterMapsToThis=None,
505 filterMap=None, centroids=False):
506 """This function takes in a reference catalog and returns a new catalog
507 with additional columns defined from the remaining function arguments.
509 Parameters
510 ----------
511 refCat : `lsst.afw.table.SimpleCatalog`
512 Reference catalog to map to new catalog
513 anyFilterMapsToThis : `str`, optional
514 Always use this reference catalog filter.
515 Mutually exclusive with `filterMap`
516 filterMap : `dict` [`str`,`str`], optional
517 Mapping of camera filter name: reference catalog filter name.
518 centroids : `bool`, optional
519 Add centroid fields to the loaded Schema. ``loadPixelBox`` expects
520 these fields to exist.
522 Returns
523 -------
524 expandedCat : `lsst.afw.table.SimpleCatalog`
525 Deep copy of input reference catalog with additional columns added
526 """
527 if anyFilterMapsToThis or filterMap:
528 ReferenceObjectLoader._addFluxAliases(refCat.schema, anyFilterMapsToThis, filterMap)
530 mapper = afwTable.SchemaMapper(refCat.schema, True)
531 mapper.addMinimalSchema(refCat.schema, True)
532 mapper.editOutputSchema().disconnectAliases()
534 if centroids:
535 # Add and initialize centroid and hasCentroid fields (these are
536 # added after loading to avoid wasting space in the saved catalogs).
537 # The new fields are automatically initialized to (nan, nan) and
538 # False so no need to set them explicitly.
539 mapper.editOutputSchema().addField("centroid_x", type=float, doReplace=True)
540 mapper.editOutputSchema().addField("centroid_y", type=float, doReplace=True)
541 mapper.editOutputSchema().addField("hasCentroid", type="Flag", doReplace=True)
542 mapper.editOutputSchema().getAliasMap().set("slot_Centroid", "centroid")
544 expandedCat = afwTable.SimpleCatalog(mapper.getOutputSchema())
545 expandedCat.setMetadata(refCat.getMetadata())
546 expandedCat.extend(refCat, mapper=mapper)
548 return expandedCat
550 @staticmethod
551 def _addFluxAliases(schema, anyFilterMapsToThis=None, filterMap=None):
552 """Add aliases for camera filter fluxes to the schema.
554 For each camFilter: refFilter in filterMap, adds these aliases:
555 <camFilter>_camFlux: <refFilter>_flux
556 <camFilter>_camFluxErr: <refFilter>_fluxErr, if the latter exists
557 or sets `anyFilterMapsToThis` in the schema.
559 Parameters
560 ----------
561 schema : `lsst.afw.table.Schema`
562 Schema for reference catalog.
563 anyFilterMapsToThis : `str`, optional
564 Always use this reference catalog filter.
565 Mutually exclusive with `filterMap`.
566 filterMap : `dict` [`str`,`str`], optional
567 Mapping of camera filter name: reference catalog filter name.
568 Mutually exclusive with `anyFilterMapsToThis`.
570 Raises
571 ------
572 RuntimeError
573 Raised if any required reference flux field is missing from the
574 schema.
575 """
576 # Fail on any truthy value for either of these.
577 if anyFilterMapsToThis and filterMap:
578 raise ValueError("anyFilterMapsToThis and filterMap are mutually exclusive!")
580 aliasMap = schema.getAliasMap()
582 if anyFilterMapsToThis is not None:
583 refFluxName = anyFilterMapsToThis + "_flux"
584 if refFluxName not in schema:
585 msg = f"Unknown reference filter for anyFilterMapsToThis='{refFluxName}'"
586 raise RuntimeError(msg)
587 aliasMap.set("anyFilterMapsToThis", refFluxName)
588 return # this is mutually exclusive with filterMap
590 def addAliasesForOneFilter(filterName, refFilterName):
591 """Add aliases for a single filter
593 Parameters
594 ----------
595 filterName : `str` (optional)
596 Camera filter name. The resulting alias name is
597 <filterName>_camFlux
598 refFilterName : `str`
599 Reference catalog filter name; the field
600 <refFilterName>_flux must exist.
601 """
602 camFluxName = filterName + "_camFlux"
603 refFluxName = refFilterName + "_flux"
604 if refFluxName not in schema:
605 raise RuntimeError("Unknown reference filter %s" % (refFluxName,))
606 aliasMap.set(camFluxName, refFluxName)
607 refFluxErrName = refFluxName + "Err"
608 if refFluxErrName in schema:
609 camFluxErrName = camFluxName + "Err"
610 aliasMap.set(camFluxErrName, refFluxErrName)
612 if filterMap is not None:
613 for filterName, refFilterName in filterMap.items():
614 addAliasesForOneFilter(filterName, refFilterName)
616 @staticmethod
617 def _makeBoxRegion(BBox, wcs, BBoxPadding):
618 outerLocalBBox = geom.Box2D(BBox)
619 innerLocalBBox = geom.Box2D(BBox)
621 # Grow the bounding box to allow for effects not fully captured by the
622 # wcs provided (which represents the current best-guess wcs solution
623 # associated with the dataset for which the calibration is to be
624 # computed using the loaded and trimmed reference catalog being defined
625 # here). These effects could include pointing errors and/or an
626 # insufficient optical distorition model for the instrument. The idea
627 # is to ensure the spherical geometric region created contains the
628 # entire region covered by the bbox.
629 # Also create an inner region that is sure to be inside the bbox.
630 outerLocalBBox.grow(BBoxPadding)
631 innerLocalBBox.grow(-1*BBoxPadding)
633 # Handle the case where the inner bounding box shrank to a zero sized
634 # region (which will be the case if the shrunken size of either
635 # dimension is less than or equal to zero). In this case, the inner
636 # bounding box is set to the original input bounding box. This is
637 # probably not the best way to handle an empty inner bounding box, but
638 # it is what the calling code currently expects.
639 if innerLocalBBox.getDimensions() == geom.Extent2D(0, 0):
640 innerLocalBBox = geom.Box2D(BBox)
642 # Convert the corners of the bounding boxes to sky coordinates.
643 innerBoxCorners = innerLocalBBox.getCorners()
644 innerSphCorners = [wcs.pixelToSky(corner).getVector() for corner in innerBoxCorners]
645 innerSkyRegion = sphgeom.ConvexPolygon(innerSphCorners)
647 outerBoxCorners = outerLocalBBox.getCorners()
648 outerSphCorners = [wcs.pixelToSky(corner).getVector() for corner in outerBoxCorners]
649 outerSkyRegion = sphgeom.ConvexPolygon(outerSphCorners)
651 return innerSkyRegion, outerSkyRegion, innerSphCorners, outerSphCorners
653 @staticmethod
654 def _calculateCircle(bbox, wcs, pixelMargin):
655 """Compute on-sky center and radius of search region.
657 Parameters
658 ----------
659 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
660 Pixel bounding box.
661 wcs : `lsst.afw.geom.SkyWcs`
662 WCS; used to convert pixel positions to sky coordinates.
663 pixelMargin : `int`
664 Padding to add to 4 all edges of the bounding box (pixels).
666 Returns
667 -------
668 results : `lsst.pipe.base.Struct`
669 A Struct containing:
671 - coord : `lsst.geom.SpherePoint`
672 ICRS center of the search region.
673 - radius : `lsst.geom.Angle`
674 Radius of the search region.
675 - bbox : `lsst.geom.Box2D`
676 Bounding box used to compute the circle.
677 """
678 bbox = geom.Box2D(bbox) # we modify the box, so use a copy
679 bbox.grow(pixelMargin)
680 coord = wcs.pixelToSky(bbox.getCenter())
681 radius = max(coord.separation(wcs.pixelToSky(pp)) for pp in bbox.getCorners())
682 return pipeBase.Struct(coord=coord, radius=radius, bbox=bbox)
684 @staticmethod
685 def getMetadataCircle(coord, radius, filterName, epoch=None):
686 """Return metadata about the reference catalog being loaded.
688 This metadata is used for reloading the catalog (e.g. for
689 reconstituting a normalized match list).
691 Parameters
692 ----------
693 coord : `lsst.geom.SpherePoint`
694 ICRS center of the search region.
695 radius : `lsst.geom.Angle`
696 Radius of the search region.
697 filterName : `str`
698 Name of the camera filter.
699 epoch : `astropy.time.Time` or `None`, optional
700 Epoch to which to correct proper motion and parallax, or `None` to
701 not apply such corrections.
703 Returns
704 -------
705 md : `lsst.daf.base.PropertyList`
706 Metadata about the catalog.
707 """
708 md = PropertyList()
709 md.add('RA', coord.getRa().asDegrees(), 'field center in degrees')
710 md.add('DEC', coord.getDec().asDegrees(), 'field center in degrees')
711 md.add('RADIUS', radius.asDegrees(), 'field radius in degrees, minimum')
712 md.add('SMATCHV', 1, 'SourceMatchVector version number')
713 md.add('FILTER', filterName, 'filter name for photometric data')
714 md.add('EPOCH', "NONE" if epoch is None else epoch.mjd, 'Epoch (TAI MJD) for catalog')
715 return md
717 def getMetadataBox(self, bbox, wcs, filterName, epoch=None,
718 bboxToSpherePadding=100):
719 """Return metadata about the load
721 This metadata is used for reloading the catalog (e.g., for
722 reconstituting a normalised match list).
724 Parameters
725 ----------
726 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
727 Bounding box for the pixels.
728 wcs : `lsst.afw.geom.SkyWcs`
729 The WCS object associated with ``bbox``.
730 filterName : `str`
731 Name of the camera filter.
732 epoch : `astropy.time.Time` or `None`, optional
733 Epoch to which to correct proper motion and parallax, or `None` to
734 not apply such corrections.
735 bboxToSpherePadding : `int`, optional
736 Padding in pixels to account for translating a set of corners into
737 a spherical (convex) boundary that is certain to encompass the
738 enitre area covered by the box.
740 Returns
741 -------
742 md : `lsst.daf.base.PropertyList`
743 The metadata detailing the search parameters used for this
744 dataset.
745 """
746 circle = self._calculateCircle(bbox, wcs, self.config.pixelMargin)
747 md = self.getMetadataCircle(circle.coord, circle.radius, filterName, epoch=epoch)
749 paddedBbox = circle.bbox
750 _, _, innerCorners, outerCorners = self._makeBoxRegion(paddedBbox, wcs, bboxToSpherePadding)
751 for box, corners in zip(("INNER", "OUTER"), (innerCorners, outerCorners)):
752 for (name, corner) in zip(("UPPER_LEFT", "UPPER_RIGHT", "LOWER_LEFT", "LOWER_RIGHT"),
753 corners):
754 md.add(f"{box}_{name}_RA", geom.SpherePoint(corner).getRa().asDegrees(), f"{box}_corner")
755 md.add(f"{box}_{name}_DEC", geom.SpherePoint(corner).getDec().asDegrees(), f"{box}_corner")
756 return md
758 def joinMatchListWithCatalog(self, matchCat, sourceCat):
759 """Relink an unpersisted match list to sources and reference objects.
761 A match list is persisted and unpersisted as a catalog of IDs
762 produced by afw.table.packMatches(), with match metadata
763 (as returned by the astrometry tasks) in the catalog's metadata
764 attribute. This method converts such a match catalog into a match
765 list, with links to source records and reference object records.
767 Parameters
768 ----------
769 matchCat : `lsst.afw.table.BaseCatalog`
770 Unpersisted packed match list.
771 ``matchCat.table.getMetadata()`` must contain match metadata,
772 as returned by the astrometry tasks.
773 sourceCat : `lsst.afw.table.SourceCatalog`
774 Source catalog. As a side effect, the catalog will be sorted
775 by ID.
777 Returns
778 -------
779 matchList : `lsst.afw.table.ReferenceMatchVector`
780 Match list.
781 """
782 return joinMatchListWithCatalogImpl(self, matchCat, sourceCat)
784 def loadPixelBox(self, bbox, wcs, filterName, epoch=None,
785 bboxToSpherePadding=100):
786 """Load reference objects that are within a pixel-based rectangular
787 region.
789 This algorithm works by creating a spherical box whose corners
790 correspond to the WCS converted corners of the input bounding box
791 (possibly padded). It then defines a filtering function which looks at
792 the pixel position of the reference objects and accepts only those that
793 lie within the specified bounding box.
795 The spherical box region and filtering function are passed to the
796 generic loadRegion method which loads and filters the reference objects
797 from the datastore and returns a single catalog containing the filtered
798 set of reference objects.
800 Parameters
801 ----------
802 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
803 Box which bounds a region in pixel space.
804 wcs : `lsst.afw.geom.SkyWcs`
805 Wcs object defining the pixel to sky (and inverse) transform for
806 the supplied ``bbox``.
807 filterName : `str`
808 Name of camera filter.
809 epoch : `astropy.time.Time` or `None`, optional
810 Epoch to which to correct proper motion and parallax, or `None`
811 to not apply such corrections.
812 bboxToSpherePadding : `int`, optional
813 Padding to account for translating a set of corners into a
814 spherical (convex) boundary that is certain to encompase the
815 enitre area covered by the box.
817 Returns
818 -------
819 output : `lsst.pipe.base.Struct`
820 Results struct with attributes:
822 ``refCat``
823 Catalog containing reference objects inside the specified
824 bounding box (padded by self.config.pixelMargin).
825 ``fluxField``
826 Name of the field containing the flux associated with
827 ``filterName``.
829 Raises
830 ------
831 RuntimeError
832 Raised if no reference catalogs could be found for the specified
833 region.
834 TypeError
835 Raised if the loaded reference catalogs do not have matching
836 schemas.
837 """
838 paddedBbox = geom.Box2D(bbox)
839 paddedBbox.grow(self.config.pixelMargin)
840 innerSkyRegion, outerSkyRegion, _, _ = self._makeBoxRegion(paddedBbox, wcs, bboxToSpherePadding)
842 def _filterFunction(refCat, region):
843 # Perform an initial "pre filter" step based on the refCat coords
844 # and the outerSkyRegion created from the self.config.pixelMargin-
845 # paddedBbox plus an "extra" padding of bboxToSpherePadding and the
846 # raw wcs. This should ensure a large enough projected area on the
847 # sky that accounts for any projection/distortion issues, but small
848 # enough to filter out loaded reference objects that lie well
849 # beyond the projected detector of interest. This step is required
850 # due to the very local nature of the wcs available for the
851 # sky <--> pixel conversions.
852 preFiltFunc = _FilterCatalog(outerSkyRegion)
853 refCat = preFiltFunc(refCat, region)
855 # Add columns to the pre-filtered reference catalog relating their
856 # coordinates to equivalent pixel positions for the wcs provided
857 # and use to populate those columns.
858 refCat = self._remapReferenceCatalogSchema(refCat, centroids=True)
859 afwTable.updateRefCentroids(wcs, refCat)
860 # No need to filter the catalog if it is entirely contained in the
861 # region defined by the inner sky region.
862 if innerSkyRegion.contains(region):
863 return refCat
864 # Create a new reference catalog, and populate it only with records
865 # that fall inside the padded bbox.
866 filteredRefCat = type(refCat)(refCat.table)
867 centroidKey = afwTable.Point2DKey(refCat.schema['centroid'])
868 for record in refCat:
869 pixCoords = record[centroidKey]
870 if paddedBbox.contains(geom.Point2D(pixCoords)):
871 filteredRefCat.append(record)
872 return filteredRefCat
873 return self.loadRegion(outerSkyRegion, filterName, filtFunc=_filterFunction, epoch=epoch)
875 def loadRegion(self, region, filterName, filtFunc=None, epoch=None):
876 """Load reference objects within a specified region.
878 This function loads the DataIds used to construct an instance of this
879 class which intersect or are contained within the specified region. The
880 reference catalogs which intersect but are not fully contained within
881 the input region are further filtered by the specified filter function.
882 This function returns a single source catalog containing all reference
883 objects inside the specified region.
885 Parameters
886 ----------
887 region : `lsst.sphgeom.Region`
888 This can be any type that is derived from `lsst.sphgeom.Region` and
889 should define the spatial region for which reference objects are to
890 be loaded.
891 filtFunc : callable or `None`, optional
892 This optional parameter should be a callable object that takes a
893 reference catalog and its corresponding region as parameters,
894 filters the catalog by some criteria and returns the filtered
895 reference catalog. If `None`, an internal filter function is used
896 which filters according to if a reference object falls within the
897 input region.
898 filterName : `str`
899 Name of camera filter.
900 epoch : `astropy.time.Time` or `None`, optional
901 Epoch to which to correct proper motion and parallax, or `None` to
902 not apply such corrections.
904 Returns
905 -------
906 output : `lsst.pipe.base.Struct`
907 Results struct with attributes:
909 ``refCat``
910 Catalog containing reference objects which intersect the
911 input region, filtered by the specified filter function.
912 ``fluxField``
913 Name of the field containing the flux associated with
914 ``filterName``.
916 Raises
917 ------
918 RuntimeError
919 Raised if no reference catalogs could be found for the specified
920 region.
921 TypeError
922 Raised if the loaded reference catalogs do not have matching
923 schemas.
924 """
925 regionLat = region.getBoundingBox().getLat()
926 regionLon = region.getBoundingBox().getLon()
927 self.log.info("Loading reference objects from %s in region bounded by "
928 "[%.8f, %.8f], [%.8f, %.8f] RA Dec",
929 # Name of refcat we're loading from is the datasetType.
930 self.refCats[0].ref.datasetType.name,
931 regionLon.getA().asDegrees(), regionLon.getB().asDegrees(),
932 regionLat.getA().asDegrees(), regionLat.getB().asDegrees())
933 if filtFunc is None:
934 filtFunc = _FilterCatalog(region)
935 # filter out all the regions supplied by the constructor that do not overlap
936 overlapList = []
937 for dataId, refCat in zip(self.dataIds, self.refCats):
938 # SphGeom supports some objects intersecting others, but is not symmetric,
939 # try the intersect operation in both directions
940 try:
941 intersects = dataId.region.intersects(region)
942 except TypeError:
943 intersects = region.intersects(dataId.region)
945 if intersects:
946 overlapList.append((dataId, refCat))
948 if len(overlapList) == 0:
949 raise RuntimeError("No reference tables could be found for input region")
951 firstCat = overlapList[0][1].get()
952 refCat = filtFunc(firstCat, overlapList[0][0].region)
953 trimmedAmount = len(firstCat) - len(refCat)
955 # Load in the remaining catalogs
956 for dataId, inputRefCat in overlapList[1:]:
957 tmpCat = inputRefCat.get()
959 if tmpCat.schema != firstCat.schema:
960 raise TypeError("Reference catalogs have mismatching schemas")
962 filteredCat = filtFunc(tmpCat, dataId.region)
963 refCat.extend(filteredCat)
964 trimmedAmount += len(tmpCat) - len(filteredCat)
966 self.log.debug("Trimmed %d refCat objects lying outside padded region, leaving %d",
967 trimmedAmount, len(refCat))
968 self.log.info("Loaded %d reference objects", len(refCat))
970 # Ensure that the loaded reference catalog is continuous in memory
971 if not refCat.isContiguous():
972 refCat = refCat.copy(deep=True)
974 self.applyProperMotions(refCat, epoch)
976 # TODO DM-34793: remove this entire if block.
977 # Verify the schema is in the correct units and has the correct version; automatically convert
978 # it with a warning if this is not the case.
979 if not hasNanojanskyFluxUnits(refCat.schema) or not getFormatVersionFromRefCat(refCat) >= 1:
980 self.log.warning("Found version 0 reference catalog with old style units in schema.")
981 self.log.warning("run `meas_algorithms/bin/convert_refcat_to_nJy.py` to convert fluxes to nJy.")
982 self.log.warning("See RFC-575 for more details.")
983 refCat = convertToNanojansky(refCat, self.log)
985 expandedCat = self._remapReferenceCatalogSchema(refCat,
986 anyFilterMapsToThis=self.config.anyFilterMapsToThis,
987 filterMap=self.config.filterMap)
989 # Ensure that the returned reference catalog is continuous in memory
990 if not expandedCat.isContiguous():
991 expandedCat = expandedCat.copy(deep=True)
993 fluxField = getRefFluxField(expandedCat.schema, filterName)
994 return pipeBase.Struct(refCat=expandedCat, fluxField=fluxField)
996 def loadSkyCircle(self, ctrCoord, radius, filterName, epoch=None):
997 """Load reference objects that lie within a circular region on the sky.
999 This method constructs a circular region from an input center and
1000 angular radius, loads reference catalogs which are contained in or
1001 intersect the circle, and filters reference catalogs which intersect
1002 down to objects which lie within the defined circle.
1004 Parameters
1005 ----------
1006 ctrCoord : `lsst.geom.SpherePoint`
1007 Point defining the center of the circular region.
1008 radius : `lsst.geom.Angle`
1009 Defines the angular radius of the circular region.
1010 filterName : `str`
1011 Name of camera filter.
1012 epoch : `astropy.time.Time` or `None`, optional
1013 Epoch to which to correct proper motion and parallax, or `None` to
1014 not apply such corrections.
1016 Returns
1017 -------
1018 output : `lsst.pipe.base.Struct`
1019 Results struct with attributes:
1021 ``refCat``
1022 Catalog containing reference objects inside the specified
1023 search circle.
1024 ``fluxField``
1025 Name of the field containing the flux associated with
1026 ``filterName``.
1027 """
1028 centerVector = ctrCoord.getVector()
1029 sphRadius = sphgeom.Angle(radius.asRadians())
1030 circularRegion = sphgeom.Circle(centerVector, sphRadius)
1031 return self.loadRegion(circularRegion, filterName, epoch=epoch)
1034def getRefFluxField(schema, filterName):
1035 """Get the name of a flux field from a schema.
1037 return the alias of "anyFilterMapsToThis", if present
1038 else:
1039 return "*filterName*_camFlux" if present
1040 else return "*filterName*_flux" if present (camera filter name
1041 matches reference filter name)
1042 else throw RuntimeError
1044 Parameters
1045 ----------
1046 schema : `lsst.afw.table.Schema`
1047 Reference catalog schema.
1048 filterName : `str`
1049 Name of camera filter.
1051 Returns
1052 -------
1053 fluxFieldName : `str`
1054 Name of flux field.
1056 Raises
1057 ------
1058 RuntimeError
1059 If an appropriate field is not found.
1060 """
1061 if not isinstance(schema, afwTable.Schema):
1062 raise RuntimeError("schema=%s is not a schema" % (schema,))
1063 try:
1064 return schema.getAliasMap().get("anyFilterMapsToThis")
1065 except LookupError:
1066 pass # try the filterMap next
1068 fluxFieldList = [filterName + "_camFlux", filterName + "_flux"]
1069 for fluxField in fluxFieldList:
1070 if fluxField in schema:
1071 return fluxField
1073 raise RuntimeError("Could not find flux field(s) %s" % (", ".join(fluxFieldList)))
1076def getRefFluxKeys(schema, filterName):
1077 """Return keys for flux and flux error.
1079 Parameters
1080 ----------
1081 schema : `lsst.afw.table.Schema`
1082 Reference catalog schema.
1083 filterName : `str`
1084 Name of camera filter.
1086 Returns
1087 -------
1088 keys : `tuple` of (`lsst.afw.table.Key`, `lsst.afw.table.Key`)
1089 Two keys:
1091 - flux key
1092 - flux error key, if present, else None
1094 Raises
1095 ------
1096 RuntimeError
1097 If flux field not found.
1098 """
1099 fluxField = getRefFluxField(schema, filterName)
1100 fluxErrField = fluxField + "Err"
1101 fluxKey = schema[fluxField].asKey()
1102 try:
1103 fluxErrKey = schema[fluxErrField].asKey()
1104 except Exception:
1105 fluxErrKey = None
1106 return (fluxKey, fluxErrKey)
1109@deprecated(reason=("This task is used in gen2 only; it will be removed after v25. "
1110 "See DM-35671 for details on updating code to avoid this warning."),
1111 version="v25.0", category=FutureWarning)
1112class LoadReferenceObjectsTask(pipeBase.Task, ReferenceObjectLoader, metaclass=abc.ABCMeta):
1113 """Abstract gen2 base class to load objects from reference catalogs.
1114 """
1115 _DefaultName = "LoadReferenceObjects"
1117 @abc.abstractmethod
1118 def loadSkyCircle(self, ctrCoord, radius, filterName, epoch=None, centroids=False):
1119 """Load reference objects that overlap a circular sky region.
1121 Parameters
1122 ----------
1123 ctrCoord : `lsst.geom.SpherePoint`
1124 ICRS center of search region.
1125 radius : `lsst.geom.Angle`
1126 Radius of search region.
1127 filterName : `str`
1128 Name of filter. This can be used for flux limit comparisons.
1129 epoch : `astropy.time.Time` or `None`, optional
1130 Epoch to which to correct proper motion and parallax, or `None` to
1131 not apply such corrections.
1132 centroids : `bool`, optional
1133 Add centroid fields to the loaded Schema. ``loadPixelBox`` expects
1134 these fields to exist.
1136 Returns
1137 -------
1138 results : `lsst.pipe.base.Struct`
1139 A Struct containing the following fields:
1140 refCat : `lsst.afw.catalog.SimpleCatalog`
1141 A catalog of reference objects with the standard
1142 schema, as documented in the main doc string for
1143 `LoadReferenceObjects`.
1144 The catalog is guaranteed to be contiguous.
1145 fluxField : `str`
1146 Name of flux field for specified `filterName`.
1148 Notes
1149 -----
1150 Note that subclasses are responsible for performing the proper motion
1151 correction, since this is the lowest-level interface for retrieving
1152 the catalog.
1153 """
1154 return
1157def joinMatchListWithCatalogImpl(refObjLoader, matchCat, sourceCat):
1158 """Relink an unpersisted match list to sources and reference
1159 objects.
1161 A match list is persisted and unpersisted as a catalog of IDs
1162 produced by afw.table.packMatches(), with match metadata
1163 (as returned by the astrometry tasks) in the catalog's metadata
1164 attribute. This method converts such a match catalog into a match
1165 list, with links to source records and reference object records.
1167 Parameters
1168 ----------
1169 refObjLoader
1170 Reference object loader to use in getting reference objects
1171 matchCat : `lsst.afw.table.BaseCatalog`
1172 Unperisted packed match list.
1173 ``matchCat.table.getMetadata()`` must contain match metadata,
1174 as returned by the astrometry tasks.
1175 sourceCat : `lsst.afw.table.SourceCatalog`
1176 Source catalog. As a side effect, the catalog will be sorted
1177 by ID.
1179 Returns
1180 -------
1181 matchList : `lsst.afw.table.ReferenceMatchVector`
1182 Match list.
1183 """
1184 matchmeta = matchCat.table.getMetadata()
1185 version = matchmeta.getInt('SMATCHV')
1186 if version != 1:
1187 raise ValueError('SourceMatchVector version number is %i, not 1.' % version)
1188 filterName = matchmeta.getString('FILTER').strip()
1189 try:
1190 epoch = matchmeta.getDouble('EPOCH')
1191 except (LookupError, TypeError):
1192 epoch = None # Not present, or not correct type means it's not set
1193 if 'RADIUS' in matchmeta:
1194 # This is a circle style metadata, call loadSkyCircle
1195 ctrCoord = geom.SpherePoint(matchmeta.getDouble('RA'),
1196 matchmeta.getDouble('DEC'), geom.degrees)
1197 rad = matchmeta.getDouble('RADIUS')*geom.degrees
1198 refCat = refObjLoader.loadSkyCircle(ctrCoord, rad, filterName, epoch=epoch).refCat
1199 elif "INNER_UPPER_LEFT_RA" in matchmeta:
1200 # This is the sky box type (only triggers in the LoadReferenceObject class, not task)
1201 # Only the outer box is required to be loaded to get the maximum region, all filtering
1202 # will be done by the unpackMatches function, and no spatial filtering needs to be done
1203 # by the refObjLoader
1204 box = []
1205 for place in ("UPPER_LEFT", "UPPER_RIGHT", "LOWER_LEFT", "LOWER_RIGHT"):
1206 coord = geom.SpherePoint(matchmeta.getDouble(f"OUTER_{place}_RA"),
1207 matchmeta.getDouble(f"OUTER_{place}_DEC"),
1208 geom.degrees).getVector()
1209 box.append(coord)
1210 outerBox = sphgeom.ConvexPolygon(box)
1211 refCat = refObjLoader.loadRegion(outerBox, filterName, epoch=epoch).refCat
1213 refCat.sort()
1214 sourceCat.sort()
1215 return afwTable.unpackMatches(matchCat, refCat, sourceCat)
1218@deprecated(reason="Base class only used for gen2 interface, and will be removed after v25.0. "
1219 "Please use ReferenceObjectLoader directly.",
1220 version="v25.0", category=FutureWarning)
1221class ReferenceObjectLoaderBase(ReferenceObjectLoader):
1222 """Stub of a deprecated class.
1224 Parameters
1225 ----------
1226 config : `lsst.pex.config.Config`
1227 Configuration for the loader.
1228 """
1229 def __init__(self, config=None, *args, **kwargs):
1230 pass
1233def applyProperMotionsImpl(log, catalog, epoch):
1234 """Apply proper motion correction to a reference catalog.
1236 Adjust position and position error in the ``catalog``
1237 for proper motion to the specified ``epoch``,
1238 modifying the catalog in place.
1240 Parameters
1241 ----------
1242 log : `lsst.log.Log` or `logging.getLogger`
1243 Log object to write to.
1244 catalog : `lsst.afw.table.SimpleCatalog`
1245 Catalog of positions, containing:
1247 - Coordinates, retrieved by the table's coordinate key.
1248 - ``coord_raErr`` : Error in Right Ascension (rad).
1249 - ``coord_decErr`` : Error in Declination (rad).
1250 - ``pm_ra`` : Proper motion in Right Ascension (rad/yr,
1251 East positive)
1252 - ``pm_raErr`` : Error in ``pm_ra`` (rad/yr), optional.
1253 - ``pm_dec`` : Proper motion in Declination (rad/yr,
1254 North positive)
1255 - ``pm_decErr`` : Error in ``pm_dec`` (rad/yr), optional.
1256 - ``epoch`` : Mean epoch of object (an astropy.time.Time)
1257 epoch : `astropy.time.Time`
1258 Epoch to which to correct proper motion.
1259 """
1260 if "epoch" not in catalog.schema or "pm_ra" not in catalog.schema or "pm_dec" not in catalog.schema:
1261 log.warning("Proper motion correction not available from catalog")
1262 return
1263 if not catalog.isContiguous():
1264 raise RuntimeError("Catalog must be contiguous")
1265 catEpoch = astropy.time.Time(catalog["epoch"], scale="tai", format="mjd")
1266 log.info("Correcting reference catalog for proper motion to %r", epoch)
1267 # Use `epoch.tai` to make sure the time difference is in TAI
1268 timeDiffsYears = (epoch.tai - catEpoch).to(astropy.units.yr).value
1269 coordKey = catalog.table.getCoordKey()
1270 # Compute the offset of each object due to proper motion
1271 # as components of the arc of a great circle along RA and Dec
1272 pmRaRad = catalog["pm_ra"]
1273 pmDecRad = catalog["pm_dec"]
1274 offsetsRaRad = pmRaRad*timeDiffsYears
1275 offsetsDecRad = pmDecRad*timeDiffsYears
1276 # Compute the corresponding bearing and arc length of each offset
1277 # due to proper motion, and apply the offset
1278 # The factor of 1e6 for computing bearing is intended as
1279 # a reasonable scale for typical values of proper motion
1280 # in order to avoid large errors for small values of proper motion;
1281 # using the offsets is another option, but it can give
1282 # needlessly large errors for short duration
1283 offsetBearingsRad = numpy.arctan2(pmDecRad*1e6, pmRaRad*1e6)
1284 offsetAmountsRad = numpy.hypot(offsetsRaRad, offsetsDecRad)
1285 for record, bearingRad, amountRad in zip(catalog, offsetBearingsRad, offsetAmountsRad):
1286 record.set(coordKey,
1287 record.get(coordKey).offset(bearing=bearingRad*geom.radians,
1288 amount=amountRad*geom.radians))
1289 # Increase error in RA and Dec based on error in proper motion
1290 if "coord_raErr" in catalog.schema:
1291 catalog["coord_raErr"] = numpy.hypot(catalog["coord_raErr"],
1292 catalog["pm_raErr"]*timeDiffsYears)
1293 if "coord_decErr" in catalog.schema:
1294 catalog["coord_decErr"] = numpy.hypot(catalog["coord_decErr"],
1295 catalog["pm_decErr"]*timeDiffsYears)