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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/).
8#
9# This program is free software: you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation, either version 3 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the LSST License Statement and
20# the GNU General Public License along with this program. If not,
21# see <https://www.lsstcorp.org/LegalNotices/>.
22#
24__all__ = ["getRefFluxField", "getRefFluxKeys", "LoadReferenceObjectsTask", "LoadReferenceObjectsConfig",
25 "ReferenceObjectLoader"]
27import abc
28import itertools
30import astropy.time
31import astropy.units
32import numpy
34import lsst.geom
35import lsst.afw.table as afwTable
36import lsst.pex.config as pexConfig
37import lsst.pex.exceptions as pexExceptions
38import lsst.pipe.base as pipeBase
39import lsst.pex.exceptions as pexExcept
40import lsst.log
41from lsst import geom
42from lsst import sphgeom
43from lsst.daf.base import PropertyList
46def isOldFluxField(name, units):
47 """Return True if this name/units combination corresponds to an
48 "old-style" reference catalog flux field.
49 """
50 unitsCheck = units != 'nJy' # (units == 'Jy' or units == '' or units == '?')
51 isFlux = name.endswith('_flux')
52 isFluxSigma = name.endswith('_fluxSigma')
53 isFluxErr = name.endswith('_fluxErr')
54 return (isFlux or isFluxSigma or isFluxErr) and unitsCheck
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` or `None`
77 Format version integer, or `None` if the catalog has no metadata
78 or the metadata does not include a "REFCAT_FORMAT_VERSION" key.
79 """
80 md = refCat.getMetadata()
81 if md is None:
82 return None
83 try:
84 return md.getScalar("REFCAT_FORMAT_VERSION")
85 except KeyError:
86 return None
89def convertToNanojansky(catalog, log, doConvert=True):
90 """Convert fluxes in a catalog from jansky to nanojansky.
92 Parameters
93 ----------
94 catalog : `lsst.afw.table.SimpleCatalog`
95 The catalog to convert.
96 log : `lsst.log.Log`
97 Log to send messages to.
98 doConvert : `bool`, optional
99 Return a converted catalog, or just identify the fields that need to be converted?
100 This supports the "write=False" mode of `bin/convert_to_nJy.py`.
102 Returns
103 -------
104 catalog : `lsst.afw.table.SimpleCatalog` or None
105 The converted catalog, or None if ``doConvert`` is False.
107 Notes
108 -----
109 Support for old units in reference catalogs will be removed after the
110 release of late calendar year 2019.
111 Use `meas_algorithms/bin/convert_to_nJy.py` to update your reference catalog.
112 """
113 # Do not share the AliasMap: for refcats, that gets created when the
114 # catalog is read from disk and should not be propagated.
115 mapper = lsst.afw.table.SchemaMapper(catalog.schema, shareAliasMap=False)
116 mapper.addMinimalSchema(lsst.afw.table.SimpleTable.makeMinimalSchema())
117 input_fields = []
118 output_fields = []
119 for field in catalog.schema:
120 oldName = field.field.getName()
121 oldUnits = field.field.getUnits()
122 if isOldFluxField(oldName, oldUnits):
123 units = 'nJy'
124 # remap Sigma flux fields to Err, so we can drop the alias
125 if oldName.endswith('_fluxSigma'):
126 name = oldName.replace('_fluxSigma', '_fluxErr')
127 else:
128 name = oldName
129 newField = lsst.afw.table.Field[field.dtype](name, field.field.getDoc(), units)
130 mapper.addMapping(field.getKey(), newField)
131 input_fields.append(field.field)
132 output_fields.append(newField)
133 else:
134 mapper.addMapping(field.getKey())
136 fluxFieldsStr = '; '.join("(%s, '%s')" % (field.getName(), field.getUnits()) for field in input_fields)
138 if doConvert:
139 newSchema = mapper.getOutputSchema()
140 output = lsst.afw.table.SimpleCatalog(newSchema)
141 output.extend(catalog, mapper=mapper)
142 for field in output_fields:
143 output[field.getName()] *= 1e9
144 log.info(f"Converted refcat flux fields to nJy (name, units): {fluxFieldsStr}")
145 return output
146 else:
147 log.info(f"Found old-style refcat flux fields (name, units): {fluxFieldsStr}")
148 return None
151class _FilterCatalog:
152 """This is a private helper class which filters catalogs by
153 row based on the row being inside the region used to initialize
154 the class.
156 Parameters
157 ----------
158 region : `lsst.sphgeom.Region`
159 The spatial region which all objects should lie within
160 """
161 def __init__(self, region):
162 self.region = region
164 def __call__(self, refCat, catRegion):
165 """This call method on an instance of this class takes in a reference
166 catalog, and the region from which the catalog was generated.
168 If the catalog region is entirely contained within the region used to
169 initialize this class, then all the entries in the catalog must be
170 within the region and so the whole catalog is returned.
172 If the catalog region is not entirely contained, then the location for
173 each record is tested against the region used to initialize the class.
174 Records which fall inside this region are added to a new catalog, and
175 this catalog is then returned.
177 Parameters
178 ---------
179 refCat : `lsst.afw.table.SourceCatalog`
180 SourceCatalog to be filtered.
181 catRegion : `lsst.sphgeom.Region`
182 Region in which the catalog was created
183 """
184 if catRegion.isWithin(self.region):
185 # no filtering needed, region completely contains refcat
186 return refCat
188 filteredRefCat = type(refCat)(refCat.table)
189 for record in refCat:
190 if self.region.contains(record.getCoord().getVector()):
191 filteredRefCat.append(record)
192 return filteredRefCat
195class ReferenceObjectLoader:
196 """ This class facilitates loading reference catalogs with gen 3 middleware
198 The middleware preflight solver will create a list of datarefs that may
199 possibly overlap a given region. These datarefs are then used to construct
200 and instance of this class. The class instance should then be passed into
201 a task which needs reference catalogs. These tasks should then determine
202 the exact region of the sky reference catalogs will be loaded for, and
203 call a corresponding method to load the reference objects.
204 """
205 def __init__(self, dataIds, refCats, config, log=None):
206 """ Constructs an instance of ReferenceObjectLoader
208 Parameters
209 ----------
210 dataIds : iterable of `lsst.daf.butler.DataIds`
211 An iterable object of DataSetRefs which point to reference catalogs
212 in a gen 3 repository
213 refCats : Iterable of `lsst.daf.butler.DeferedDatasetHandle`
214 Handles to load refCats on demand
215 log : `lsst.log.Log`
216 Logger object used to write out messages. If `None` (default) the default
217 lsst logger will be used
219 """
220 self.dataIds = dataIds
221 self.refCats = refCats
222 self.log = log or lsst.log.Log.getDefaultLogger()
223 self.config = config
225 @staticmethod
226 def _makeBoxRegion(BBox, wcs, BBoxPadding):
227 outerLocalBBox = geom.Box2D(BBox)
228 innerLocalBBox = geom.Box2D(BBox)
230 # Grow the bounding box to make sure the spherical geometry bbox will contain
231 # the same region, as non-padded boxes may contain different regions because of optical distortion.
232 # Also create an inner region that is sure to be inside the bbox
233 outerLocalBBox.grow(BBoxPadding)
234 innerLocalBBox.grow(-1*BBoxPadding)
236 # Handle the fact that the inner bounding box shrunk to a zero sized region in at least one
237 # dimension, in which case all reference catalogs must be checked fully against the input
238 # bounding box
239 if innerLocalBBox.getDimensions() == geom.Extent2D(0, 0):
240 innerSkyRegion = sphgeom.Box()
241 else:
242 innerBoxCorners = innerLocalBBox.getCorners()
243 innerSphCorners = [wcs.pixelToSky(corner).getVector() for corner in innerBoxCorners]
245 innerSkyRegion = sphgeom.ConvexPolygon(innerSphCorners)
247 # Convert the corners of the box to sky coordinates
248 outerBoxCorners = outerLocalBBox.getCorners()
249 outerSphCorners = [wcs.pixelToSky(corner).getVector() for corner in outerBoxCorners]
251 outerSkyRegion = sphgeom.ConvexPolygon(outerSphCorners)
253 return innerSkyRegion, outerSkyRegion, innerSphCorners, outerSphCorners
255 def loadPixelBox(self, bbox, wcs, filterName=None, epoch=None, photoCalib=None, bboxPadding=100):
256 """Load reference objects that are within a pixel-based rectangular region
258 This algorithm works by creating a spherical box whose corners correspond
259 to the WCS converted corners of the input bounding box (possibly padded).
260 It then defines a filtering function which will look at a reference
261 objects pixel position and accept objects that lie within the specified
262 bounding box.
264 The spherical box region and filtering function are passed to the generic
265 loadRegion method which will load and filter the reference objects from
266 the datastore and return a single catalog containing all reference objects
268 Parameters
269 ----------
270 bbox : `lsst.geom.box2I`
271 Box which bounds a region in pixel space
272 wcs : `lsst.afw.geom.SkyWcs`
273 Wcs object defining the pixel to sky (and inverse) transform for the space
274 of pixels of the supplied bbox
275 filterName : `str`
276 Name of camera filter, or None or blank for the default filter
277 epoch : `astropy.time.Time` (optional)
278 Epoch to which to correct proper motion and parallax,
279 or None to not apply such corrections.
280 photoCalib : None
281 Deprecated and ignored, only included for api compatibility
282 bboxPadding : `int`
283 Number describing how much to pad the input bbox by (in pixels), defaults
284 to 100. This parameter is necessary because optical distortions in telescopes
285 can cause a rectangular pixel grid to map into a non "rectangular" spherical
286 region in sky coordinates. This padding is used to create a spherical
287 "rectangle", which will for sure enclose the input box. This padding is only
288 used to determine if the reference catalog for a sky patch will be loaded from
289 the data store, this function will filter out objects which lie within the
290 padded region but fall outside the input bounding box region.
292 Returns
293 -------
294 referenceCatalog : `lsst.afw.table.SimpleCatalog`
295 Catalog containing reference objects inside the specified bounding box
297 Raises
298 ------
299 `lsst.pex.exception.RuntimeError`
300 Raised if no reference catalogs could be found for the specified region
302 `lsst.pex.exception.TypeError`
303 Raised if the loaded reference catalogs do not have matching schemas
304 """
305 innerSkyRegion, outerSkyRegion, _, _ = self._makeBoxRegion(bbox, wcs, bboxPadding)
307 def _filterFunction(refCat, region):
308 # Add columns to the reference catalog relating to center positions and use afwTable
309 # to populate those columns
310 refCat = self.remapReferenceCatalogSchema(refCat, position=True)
311 afwTable.updateRefCentroids(wcs, refCat)
312 # no need to filter the catalog if it is sure that it is entirely contained in the region
313 # defined by given bbox
314 if innerSkyRegion.contains(region):
315 return refCat
316 # Create a new reference catalog, and populate it with records which fall inside the bbox
317 filteredRefCat = type(refCat)(refCat.table)
318 centroidKey = afwTable.Point2DKey(refCat.schema['centroid'])
319 for record in refCat:
320 pixCoords = record[centroidKey]
321 if bbox.contains(geom.Point2I(pixCoords)):
322 filteredRefCat.append(record)
323 return filteredRefCat
324 return self.loadRegion(outerSkyRegion, filtFunc=_filterFunction, epoch=epoch, filterName=filterName)
326 def loadRegion(self, region, filtFunc=None, filterName=None, epoch=None):
327 """ Load reference objects within a specified region
329 This function loads the DataIds used to construct an instance of this class
330 which intersect or are contained within the specified region. The reference
331 catalogs which intersect but are not fully contained within the input region are
332 further filtered by the specified filter function. This function will return a
333 single source catalog containing all reference objects inside the specified region.
335 Parameters
336 ----------
337 region : `lsst.sphgeom.Region`
338 This can be any type that is derived from `lsst.sphgeom.region` and should
339 define the spatial region for which reference objects are to be loaded.
340 filtFunc : callable
341 This optional parameter should be a callable object that takes a reference
342 catalog and its corresponding region as parameters, filters the catalog by
343 some criteria and returns the filtered reference catalog. If the value is
344 left as the default (None) than an internal filter function is used which
345 filters according to if a reference object falls within the input region.
346 filterName : `str`
347 Name of camera filter, or None or blank for the default filter
348 epoch : `astropy.time.Time` (optional)
349 Epoch to which to correct proper motion and parallax,
350 or None to not apply such corrections.
352 Returns
353 -------
354 referenceCatalog : `lsst.afw.table.SourceCatalog`
355 Catalog containing reference objects which intersect the input region,
356 filtered by the specified filter function
358 Raises
359 ------
360 `lsst.pex.exception.RuntimeError`
361 Raised if no reference catalogs could be found for the specified region
363 `lsst.pex.exception.TypeError`
364 Raised if the loaded reference catalogs do not have matching schemas
366 """
367 regionBounding = region.getBoundingBox()
368 self.log.info("Loading reference objects from region bounded by {}, {} lat lon".format(
369 regionBounding.getLat(), regionBounding.getLon()))
370 if filtFunc is None:
371 filtFunc = _FilterCatalog(region)
372 # filter out all the regions supplied by the constructor that do not overlap
373 overlapList = []
374 for dataId, refCat in zip(self.dataIds, self.refCats):
375 # SphGeom supports some objects intersecting others, but is not symmetric,
376 # try the intersect operation in both directions
377 try:
378 intersects = dataId.region.intersects(region)
379 except TypeError:
380 intersects = region.intersects(dataId.region)
382 if intersects:
383 overlapList.append((dataId, refCat))
385 if len(overlapList) == 0:
386 raise pexExceptions.RuntimeError("No reference tables could be found for input region")
388 firstCat = overlapList[0][1].get()
389 refCat = filtFunc(firstCat, overlapList[0][0].region)
390 trimmedAmount = len(firstCat) - len(refCat)
392 # Load in the remaining catalogs
393 for dataId, inputRefCat in overlapList[1:]:
394 tmpCat = inputRefCat.get()
396 if tmpCat.schema != firstCat.schema:
397 raise pexExceptions.TypeError("Reference catalogs have mismatching schemas")
399 filteredCat = filtFunc(tmpCat, dataId.region)
400 refCat.extend(filteredCat)
401 trimmedAmount += len(tmpCat) - len(filteredCat)
403 self.log.debug(f"Trimmed {trimmedAmount} out of region objects, leaving {len(refCat)}")
404 self.log.info(f"Loaded {len(refCat)} reference objects")
406 # Ensure that the loaded reference catalog is continuous in memory
407 if not refCat.isContiguous():
408 refCat = refCat.copy(deep=True)
410 if epoch is not None and "pm_ra" in refCat.schema:
411 # check for a catalog in a non-standard format
412 if isinstance(refCat.schema["pm_ra"].asKey(), lsst.afw.table.KeyAngle):
413 applyProperMotionsImpl(self.log, refCat, epoch)
414 else:
415 self.log.warn("Catalog pm_ra field is not an Angle; not applying proper motion")
417 # Verify the schema is in the correct units and has the correct version; automatically convert
418 # it with a warning if this is not the case.
419 if not hasNanojanskyFluxUnits(refCat.schema) or not getFormatVersionFromRefCat(refCat) >= 1:
420 self.log.warn("Found version 0 reference catalog with old style units in schema.")
421 self.log.warn("run `meas_algorithms/bin/convert_refcat_to_nJy.py` to convert fluxes to nJy.")
422 self.log.warn("See RFC-575 for more details.")
423 refCat = convertToNanojansky(refCat, self.log)
425 expandedCat = self.remapReferenceCatalogSchema(refCat, position=True)
427 # Add flux aliases
428 expandedCat = self.addFluxAliases(expandedCat, self.config.defaultFilter, self.config.filterMap)
430 # Ensure that the returned reference catalog is continuous in memory
431 if not expandedCat.isContiguous():
432 expandedCat = expandedCat.copy(deep=True)
434 fluxField = getRefFluxField(schema=expandedCat.schema, filterName=filterName)
435 return pipeBase.Struct(refCat=expandedCat, fluxField=fluxField)
437 def loadSkyCircle(self, ctrCoord, radius, filterName=None, epoch=None):
438 """Load reference objects that lie within a circular region on the sky
440 This method constructs a circular region from an input center and angular radius,
441 loads reference catalogs which are contained in or intersect the circle, and
442 filters reference catalogs which intersect down to objects which lie within
443 the defined circle.
445 Parameters
446 ----------
447 ctrCoord : `lsst.geom.SpherePoint`
448 Point defining the center of the circular region
449 radius : `lsst.geom.Angle`
450 Defines the angular radius of the circular region
451 filterName : `str`
452 Name of camera filter, or None or blank for the default filter
453 epoch : `astropy.time.Time` (optional)
454 Epoch to which to correct proper motion and parallax,
455 or None to not apply such corrections.
457 Returns
458 -------
459 referenceCatalog : `lsst.afw.table.SourceCatalog`
460 Catalog containing reference objects inside the specified bounding box
462 Raises
463 ------
464 `lsst.pex.exception.RuntimeError`
465 Raised if no reference catalogs could be found for the specified region
467 `lsst.pex.exception.TypeError`
468 Raised if the loaded reference catalogs do not have matching schemas
470 """
471 centerVector = ctrCoord.getVector()
472 sphRadius = sphgeom.Angle(radius.asRadians())
473 circularRegion = sphgeom.Circle(centerVector, sphRadius)
474 return self.loadRegion(circularRegion, filterName=filterName, epoch=epoch)
476 def joinMatchListWithCatalog(self, matchCat, sourceCat):
477 """Relink an unpersisted match list to sources and reference
478 objects.
480 A match list is persisted and unpersisted as a catalog of IDs
481 produced by afw.table.packMatches(), with match metadata
482 (as returned by the astrometry tasks) in the catalog's metadata
483 attribute. This method converts such a match catalog into a match
484 list, with links to source records and reference object records.
486 Parameters
487 ----------
488 matchCat : `lsst.afw.table.BaseCatalog`
489 Unpersisted packed match list.
490 ``matchCat.table.getMetadata()`` must contain match metadata,
491 as returned by the astrometry tasks.
492 sourceCat : `lsst.afw.table.SourceCatalog`
493 Source catalog. As a side effect, the catalog will be sorted
494 by ID.
496 Returns
497 -------
498 matchList : `lsst.afw.table.ReferenceMatchVector`
499 Match list.
500 """
501 return joinMatchListWithCatalogImpl(self, matchCat, sourceCat)
503 @classmethod
504 def getMetadataBox(cls, bbox, wcs, filterName=None, photoCalib=None, epoch=None, bboxPadding=100):
505 """Return metadata about the load
507 This metadata is used for reloading the catalog (e.g., for
508 reconstituting a normalised match list.)
510 Parameters
511 ----------
512 bbox : `lsst.geom.Box2I`
513 Bounding bos for the pixels
514 wcs : `lsst.afw.geom.SkyWcs
515 WCS object
516 filterName : `str` or None
517 filterName of the camera filter, or None or blank for the default filter
518 photoCalib : None
519 Deprecated, only included for api compatibility
520 epoch : `astropy.time.Time` (optional)
521 Epoch to which to correct proper motion and parallax,
522 or None to not apply such corrections.
523 bboxPadding : `int`
524 Number describing how much to pad the input bbox by (in pixels), defaults
525 to 100. This parameter is necessary because optical distortions in telescopes
526 can cause a rectangular pixel grid to map into a non "rectangular" spherical
527 region in sky coordinates. This padding is used to create a spherical
528 "rectangle", which will for sure enclose the input box. This padding is only
529 used to determine if the reference catalog for a sky patch will be loaded from
530 the data store, this function will filter out objects which lie within the
531 padded region but fall outside the input bounding box region.
532 Returns
533 -------
534 md : `lsst.daf.base.PropertyList`
535 """
536 _, _, innerCorners, outerCorners = cls._makeBoxRegion(bbox, wcs, bboxPadding)
537 md = PropertyList()
538 for box, corners in zip(("INNER", "OUTER"), (innerCorners, outerCorners)):
539 for (name, corner) in zip(("UPPER_LEFT", "UPPER_RIGHT", "LOWER_LEFT", "LOWER_RIGHT"),
540 corners):
541 md.add(f"{box}_{name}_RA", geom.SpherePoint(corner).getRa().asDegrees(), f"{box}_corner")
542 md.add(f"{box}_{name}_DEC", geom.SpherePoint(corner).getDec().asDegrees(), f"{box}_corner")
543 md.add("SMATCHV", 1, 'SourceMatchVector version number')
544 filterName = "UNKNOWN" if filterName is None else str(filterName)
545 md.add('FILTER', filterName, 'filter name for photometric data')
546 md.add('EPOCH', "NONE" if epoch is None else epoch.mjd, 'Epoch (TAI MJD) for catalog')
547 return md
549 @staticmethod
550 def getMetadataCircle(coord, radius, filterName, photoCalib=None, epoch=None):
551 """Return metadata about the load
553 This metadata is used for reloading the catalog (e.g. for reconstituting
554 a normalized match list.)
556 Parameters
557 ----------
558 coord : `lsst.geom.SpherePoint`
559 ICRS center of a circle
560 radius : `lsst.geom.angle`
561 radius of a circle
562 filterName : `str` or None
563 filterName of the camera filter, or None or blank for the default filter
564 photoCalib : None
565 Deprecated, only included for api compatibility
566 epoch : `astropy.time.Time` (optional)
567 Epoch to which to correct proper motion and parallax,
568 or None to not apply such corrections.
570 Returns
571 -------
572 md : `lsst.daf.base.PropertyList`
573 """
574 md = PropertyList()
575 md.add('RA', coord.getRa().asDegrees(), 'field center in degrees')
576 md.add('DEC', coord.getDec().asDegrees(), 'field center in degrees')
577 md.add('RADIUS', radius.asDegrees(), 'field radius in degrees, minimum')
578 md.add('SMATCHV', 1, 'SourceMatchVector version number')
579 filterName = "UNKNOWN" if filterName is None else str(filterName)
580 md.add('FILTER', filterName, 'filter name for photometric data')
581 md.add('EPOCH', "NONE" if epoch is None else epoch.mjd, 'Epoch (TAI MJD) for catalog')
582 return md
584 @staticmethod
585 def addFluxAliases(refCat, defaultFilter, filterReferenceMap):
586 """This function creates a new catalog containing the information of the input refCat
587 as well as added flux columns and aliases between camera and reference flux.
589 Parameters
590 ----------
591 refCat : `lsst.afw.table.SimpleCatalog`
592 Catalog of reference objects
593 defaultFilter : `str`
594 Name of the default reference filter
595 filterReferenceMap : `dict` of `str`
596 Dictionary with keys corresponding to a filter name, and values which
597 correspond to the name of the reference filter.
599 Returns
600 -------
601 refCat : `lsst.afw.table.SimpleCatalog`
602 Reference catalog with columns added to track reference filters
604 Raises
605 ------
606 `RuntimeError`
607 If specified reference filter name is not a filter specifed as a key in the
608 reference filter map.
609 """
610 refCat = ReferenceObjectLoader.remapReferenceCatalogSchema(refCat,
611 filterNameList=filterReferenceMap.keys())
612 aliasMap = refCat.schema.getAliasMap()
613 if filterReferenceMap is None:
614 filterReferenceMap = {}
615 for filterName, refFilterName in itertools.chain([(None, defaultFilter)],
616 filterReferenceMap.items()):
617 if refFilterName:
618 camFluxName = filterName + "_camFlux" if filterName is not None else "camFlux"
619 refFluxName = refFilterName + "_flux"
620 if refFluxName not in refCat.schema:
621 raise RuntimeError("Unknown reference filter %s" % (refFluxName,))
622 aliasMap.set(camFluxName, refFluxName)
624 refFluxErrName = refFluxName + "Err"
625 camFluxErrName = camFluxName + "Err"
626 aliasMap.set(camFluxErrName, refFluxErrName)
628 return refCat
630 @staticmethod
631 def remapReferenceCatalogSchema(refCat, *, filterNameList=None, position=False, photometric=False):
632 """This function takes in a reference catalog and creates a new catalog with additional
633 columns defined the remaining function arguments.
635 Parameters
636 ----------
637 refCat : `lsst.afw.table.SimpleCatalog`
638 Reference catalog to map to new catalog
640 Returns
641 -------
642 expandedCat : `lsst.afw.table.SimpleCatalog`
643 Deep copy of input reference catalog with additional columns added
644 """
645 mapper = afwTable.SchemaMapper(refCat.schema, True)
646 mapper.addMinimalSchema(refCat.schema, True)
647 mapper.editOutputSchema().disconnectAliases()
648 if filterNameList:
649 for filterName in filterNameList:
650 mapper.editOutputSchema().addField(f"{filterName}_flux",
651 type=numpy.float64,
652 doc=f"flux in filter {filterName}",
653 units="Jy"
654 )
655 mapper.editOutputSchema().addField(f"{filterName}_fluxErr",
656 type=numpy.float64,
657 doc=f"flux uncertanty in filter {filterName}",
658 units="Jy"
659 )
661 if position:
662 mapper.editOutputSchema().addField("centroid_x", type=float, doReplace=True)
663 mapper.editOutputSchema().addField("centroid_y", type=float, doReplace=True)
664 mapper.editOutputSchema().addField("hasCentroid", type="Flag", doReplace=True)
665 mapper.editOutputSchema().getAliasMap().set("slot_Centroid", "centroid")
667 if photometric:
668 mapper.editOutputSchema().addField("photometric",
669 type="Flag",
670 doc="set if the object can be used for photometric"
671 "calibration",
672 )
673 mapper.editOutputSchema().addField("resolved",
674 type="Flag",
675 doc="set if the object is spatially resolved"
676 )
677 mapper.editOutputSchema().addField("variable",
678 type="Flag",
679 doc="set if the object has variable brightness"
680 )
682 expandedCat = afwTable.SimpleCatalog(mapper.getOutputSchema())
683 expandedCat.setMetadata(refCat.getMetadata())
684 expandedCat.extend(refCat, mapper=mapper)
686 return expandedCat
689def getRefFluxField(schema, filterName=None):
690 """Get the name of a flux field from a schema.
692 return the alias of "anyFilterMapsToThis", if present
693 else if filterName is specified:
694 return "*filterName*_camFlux" if present
695 else return "*filterName*_flux" if present (camera filter name
696 matches reference filter name)
697 else throw RuntimeError
698 else:
699 return "camFlux", if present,
700 else throw RuntimeError
702 Parameters
703 ----------
704 schema : `lsst.afw.table.Schema`
705 Reference catalog schema.
706 filterName : `str`, optional
707 Name of camera filter. If not specified, ``defaultFilter`` needs to be
708 set in the refcat loader config.
710 Returns
711 -------
712 fluxFieldName : `str`
713 Name of flux field.
715 Raises
716 ------
717 RuntimeError
718 If an appropriate field is not found.
719 """
720 if not isinstance(schema, afwTable.Schema):
721 raise RuntimeError("schema=%s is not a schema" % (schema,))
722 try:
723 return schema.getAliasMap().get("anyFilterMapsToThis")
724 except LookupError:
725 pass # try the filterMap next
727 if filterName:
728 fluxFieldList = [filterName + "_camFlux", filterName + "_flux"]
729 else:
730 fluxFieldList = ["camFlux"]
731 for fluxField in fluxFieldList:
732 if fluxField in schema:
733 return fluxField
735 raise RuntimeError("Could not find flux field(s) %s" % (", ".join(fluxFieldList)))
738def getRefFluxKeys(schema, filterName=None):
739 """Return keys for flux and flux error.
741 Parameters
742 ----------
743 schema : `lsst.afw.table.Schema`
744 Reference catalog schema.
745 filterName : `str`
746 Name of camera filter.
748 Returns
749 -------
750 keys : `tuple` of (`lsst.afw.table.Key`, `lsst.afw.table.Key`)
751 Two keys:
753 - flux key
754 - flux error key, if present, else None
756 Raises
757 ------
758 RuntimeError
759 If flux field not found.
760 """
761 fluxField = getRefFluxField(schema, filterName)
762 fluxErrField = fluxField + "Err"
763 fluxKey = schema[fluxField].asKey()
764 try:
765 fluxErrKey = schema[fluxErrField].asKey()
766 except Exception:
767 fluxErrKey = None
768 return (fluxKey, fluxErrKey)
771class LoadReferenceObjectsConfig(pexConfig.Config):
772 pixelMargin = pexConfig.RangeField(
773 doc="Padding to add to 4 all edges of the bounding box (pixels)",
774 dtype=int,
775 default=300,
776 min=0,
777 )
778 defaultFilter = pexConfig.Field(
779 doc=("Default reference catalog filter to use if filter not specified in exposure;"
780 " if blank then filter must be specified in exposure."),
781 dtype=str,
782 default="",
783 deprecated="defaultFilter is deprecated by RFC-716. Will be removed after v22."
784 )
785 anyFilterMapsToThis = pexConfig.Field(
786 doc=("Always use this reference catalog filter, no matter whether or what filter name is "
787 "supplied to the loader. Effectively a trivial filterMap: map all filter names to this filter."
788 " This can be set for purely-astrometric catalogs (e.g. Gaia DR2) where there is only one "
789 "reasonable choice for every camera filter->refcat mapping, but not for refcats used for "
790 "photometry, which need a filterMap and/or colorterms/transmission corrections."),
791 dtype=str,
792 default=None,
793 optional=True
794 )
795 filterMap = pexConfig.DictField(
796 doc=("Mapping of camera filter name: reference catalog filter name; "
797 "each reference filter must exist in the refcat."
798 " Note that this does not perform any bandpass corrections: it is just a lookup."),
799 keytype=str,
800 itemtype=str,
801 default={},
802 )
803 requireProperMotion = pexConfig.Field(
804 doc="Require that the fields needed to correct proper motion "
805 "(epoch, pm_ra and pm_dec) are present?",
806 dtype=bool,
807 default=False,
808 )
810 def validate(self):
811 super().validate()
812 if self.filterMap != {} and self.anyFilterMapsToThis is not None:
813 msg = "`filterMap` and `anyFilterMapsToThis` are mutually exclusive"
814 raise pexConfig.FieldValidationError(LoadReferenceObjectsConfig.anyFilterMapsToThis,
815 self, msg)
818class LoadReferenceObjectsTask(pipeBase.Task, metaclass=abc.ABCMeta):
819 r"""Abstract base class to load objects from reference catalogs
820 """
821 ConfigClass = LoadReferenceObjectsConfig
822 _DefaultName = "LoadReferenceObjects"
824 def __init__(self, butler=None, *args, **kwargs):
825 """Construct a LoadReferenceObjectsTask
827 Parameters
828 ----------
829 butler : `lsst.daf.persistence.Butler`
830 Data butler, for access reference catalogs.
831 """
832 pipeBase.Task.__init__(self, *args, **kwargs)
833 self.butler = butler
835 @pipeBase.timeMethod
836 def loadPixelBox(self, bbox, wcs, filterName=None, photoCalib=None, epoch=None):
837 """Load reference objects that overlap a rectangular pixel region.
839 Parameters
840 ----------
841 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
842 Bounding box for pixels.
843 wcs : `lsst.afw.geom.SkyWcs`
844 WCS; used to convert pixel positions to sky coordinates
845 and vice-versa.
846 filterName : `str`
847 Name of filter, or `None` or `""` for the default filter.
848 This is used for flux values in case we have flux limits
849 (which are not yet implemented).
850 photoCalib : `lsst.afw.image.PhotoCalib` (optional)
851 Calibration, or `None` if unknown.
852 epoch : `astropy.time.Time` (optional)
853 Epoch to which to correct proper motion and parallax,
854 or None to not apply such corrections.
856 Returns
857 -------
858 results : `lsst.pipe.base.Struct`
859 A Struct containing the following fields:
860 refCat : `lsst.afw.catalog.SimpleCatalog`
861 A catalog of reference objects with the standard
862 schema, as documented in the main doc string for
863 `LoadReferenceObjects`.
864 The catalog is guaranteed to be contiguous.
865 fluxField : `str`
866 Name of flux field for specified `filterName`.
868 Notes
869 -----
870 The search algorithm works by searching in a region in sky
871 coordinates whose center is the center of the bbox and radius
872 is large enough to just include all 4 corners of the bbox.
873 Stars that lie outside the bbox are then trimmed from the list.
874 """
875 circle = self._calculateCircle(bbox, wcs)
877 # find objects in circle
878 self.log.info("Loading reference objects using center %s and radius %s deg" %
879 (circle.coord, circle.radius.asDegrees()))
880 loadRes = self.loadSkyCircle(circle.coord, circle.radius, filterName=filterName, epoch=epoch,
881 centroids=True)
882 refCat = loadRes.refCat
883 numFound = len(refCat)
885 # trim objects outside bbox
886 refCat = self._trimToBBox(refCat=refCat, bbox=circle.bbox, wcs=wcs)
887 numTrimmed = numFound - len(refCat)
888 self.log.debug("trimmed %d out-of-bbox objects, leaving %d", numTrimmed, len(refCat))
889 self.log.info("Loaded %d reference objects", len(refCat))
891 # make sure catalog is contiguous
892 if not refCat.isContiguous():
893 loadRes.refCat = refCat.copy(deep=True)
895 return loadRes
897 @abc.abstractmethod
898 def loadSkyCircle(self, ctrCoord, radius, filterName=None, epoch=None, centroids=False):
899 """Load reference objects that overlap a circular sky region.
901 Parameters
902 ----------
903 ctrCoord : `lsst.geom.SpherePoint`
904 ICRS center of search region.
905 radius : `lsst.geom.Angle`
906 Radius of search region.
907 filterName : `str` (optional)
908 Name of filter, or `None` or `""` for the default filter.
909 This is used for flux values in case we have flux limits
910 (which are not yet implemented).
911 epoch : `astropy.time.Time` (optional)
912 Epoch to which to correct proper motion and parallax,
913 or None to not apply such corrections.
914 centroids : `bool` (optional)
915 Add centroid fields to the loaded Schema. ``loadPixelBox`` expects
916 these fields to exist.
918 Returns
919 -------
920 results : `lsst.pipe.base.Struct`
921 A Struct containing the following fields:
922 refCat : `lsst.afw.catalog.SimpleCatalog`
923 A catalog of reference objects with the standard
924 schema, as documented in the main doc string for
925 `LoadReferenceObjects`.
926 The catalog is guaranteed to be contiguous.
927 fluxField : `str`
928 Name of flux field for specified `filterName`.
930 Notes
931 -----
932 Note that subclasses are responsible for performing the proper motion
933 correction, since this is the lowest-level interface for retrieving
934 the catalog.
935 """
936 return
938 @staticmethod
939 def _trimToBBox(refCat, bbox, wcs):
940 """Remove objects outside a given pixel bounding box and set
941 centroid and hasCentroid fields.
943 Parameters
944 ----------
945 refCat : `lsst.afw.table.SimpleCatalog`
946 A catalog of objects. The schema must include fields
947 "coord", "centroid" and "hasCentroid".
948 The "coord" field is read.
949 The "centroid" and "hasCentroid" fields are set.
950 bbox : `lsst.geom.Box2D`
951 Pixel region
952 wcs : `lsst.afw.geom.SkyWcs`
953 WCS; used to convert sky coordinates to pixel positions.
955 Returns
956 -------
957 catalog : `lsst.afw.table.SimpleCatalog`
958 Reference objects in the bbox, with centroid and
959 hasCentroid fields set.
960 """
961 afwTable.updateRefCentroids(wcs, refCat)
962 centroidKey = afwTable.Point2DKey(refCat.schema["centroid"])
963 retStarCat = type(refCat)(refCat.table)
964 for star in refCat:
965 point = star.get(centroidKey)
966 if bbox.contains(point):
967 retStarCat.append(star)
968 return retStarCat
970 def _addFluxAliases(self, schema):
971 """Add aliases for camera filter fluxes to the schema.
973 If self.config.defaultFilter then adds these aliases:
974 camFlux: <defaultFilter>_flux
975 camFluxErr: <defaultFilter>_fluxErr, if the latter exists
977 For each camFilter: refFilter in self.config.filterMap adds these aliases:
978 <camFilter>_camFlux: <refFilter>_flux
979 <camFilter>_camFluxErr: <refFilter>_fluxErr, if the latter exists
981 Parameters
982 ----------
983 schema : `lsst.afw.table.Schema`
984 Schema for reference catalog.
986 Raises
987 ------
988 RuntimeError
989 If any reference flux field is missing from the schema.
990 """
991 aliasMap = schema.getAliasMap()
993 if self.config.anyFilterMapsToThis is not None:
994 refFluxName = self.config.anyFilterMapsToThis + "_flux"
995 if refFluxName not in schema:
996 msg = f"Unknown reference filter for anyFilterMapsToThis='{refFluxName}'"
997 raise RuntimeError(msg)
998 aliasMap.set("anyFilterMapsToThis", refFluxName)
999 return # this is mutually exclusive with filterMap
1001 def addAliasesForOneFilter(filterName, refFilterName):
1002 """Add aliases for a single filter
1004 Parameters
1005 ----------
1006 filterName : `str` (optional)
1007 Camera filter name. The resulting alias name is
1008 <filterName>_camFlux, or simply "camFlux" if `filterName`
1009 is `None` or `""`.
1010 refFilterName : `str`
1011 Reference catalog filter name; the field
1012 <refFilterName>_flux must exist.
1013 """
1014 camFluxName = filterName + "_camFlux" if filterName is not None else "camFlux"
1015 refFluxName = refFilterName + "_flux"
1016 if refFluxName not in schema:
1017 raise RuntimeError("Unknown reference filter %s" % (refFluxName,))
1018 aliasMap.set(camFluxName, refFluxName)
1019 refFluxErrName = refFluxName + "Err"
1020 if refFluxErrName in schema:
1021 camFluxErrName = camFluxName + "Err"
1022 aliasMap.set(camFluxErrName, refFluxErrName)
1024 if self.config.defaultFilter:
1025 addAliasesForOneFilter(None, self.config.defaultFilter)
1027 for filterName, refFilterName in self.config.filterMap.items():
1028 addAliasesForOneFilter(filterName, refFilterName)
1030 @staticmethod
1031 def makeMinimalSchema(filterNameList, *, addCentroid=False,
1032 addIsPhotometric=False, addIsResolved=False,
1033 addIsVariable=False, coordErrDim=2,
1034 addProperMotion=False, properMotionErrDim=2,
1035 addParallax=False):
1036 """Make a standard schema for reference object catalogs.
1038 Parameters
1039 ----------
1040 filterNameList : `list` of `str`
1041 List of filter names. Used to create <filterName>_flux fields.
1042 addIsPhotometric : `bool`
1043 If True then add field "photometric".
1044 addIsResolved : `bool`
1045 If True then add field "resolved".
1046 addIsVariable : `bool`
1047 If True then add field "variable".
1048 coordErrDim : `int`
1049 Number of coord error fields; must be one of 0, 2, 3:
1051 - If 2 or 3: add fields "coord_raErr" and "coord_decErr".
1052 - If 3: also add field "coord_radecErr".
1053 addProperMotion : `bool`
1054 If True add fields "epoch", "pm_ra", "pm_dec" and "pm_flag".
1055 properMotionErrDim : `int`
1056 Number of proper motion error fields; must be one of 0, 2, 3;
1057 ignored if addProperMotion false:
1058 - If 2 or 3: add fields "pm_raErr" and "pm_decErr".
1059 - If 3: also add field "pm_radecErr".
1060 addParallax : `bool`
1061 If True add fields "epoch", "parallax", "parallaxErr"
1062 and "parallax_flag".
1064 Returns
1065 -------
1066 schema : `lsst.afw.table.Schema`
1067 Schema for reference catalog, an
1068 `lsst.afw.table.SimpleCatalog`.
1070 Notes
1071 -----
1072 Reference catalogs support additional covariances, such as
1073 covariance between RA and proper motion in declination,
1074 that are not supported by this method, but can be added after
1075 calling this method.
1076 """
1077 schema = afwTable.SimpleTable.makeMinimalSchema()
1078 if addCentroid:
1079 afwTable.Point2DKey.addFields(
1080 schema,
1081 "centroid",
1082 "centroid on an exposure, if relevant",
1083 "pixel",
1084 )
1085 schema.addField(
1086 field="hasCentroid",
1087 type="Flag",
1088 doc="is position known?",
1089 )
1090 for filterName in filterNameList:
1091 schema.addField(
1092 field="%s_flux" % (filterName,),
1093 type=numpy.float64,
1094 doc="flux in filter %s" % (filterName,),
1095 units="nJy",
1096 )
1097 for filterName in filterNameList:
1098 schema.addField(
1099 field="%s_fluxErr" % (filterName,),
1100 type=numpy.float64,
1101 doc="flux uncertainty in filter %s" % (filterName,),
1102 units="nJy",
1103 )
1104 if addIsPhotometric:
1105 schema.addField(
1106 field="photometric",
1107 type="Flag",
1108 doc="set if the object can be used for photometric calibration",
1109 )
1110 if addIsResolved:
1111 schema.addField(
1112 field="resolved",
1113 type="Flag",
1114 doc="set if the object is spatially resolved",
1115 )
1116 if addIsVariable:
1117 schema.addField(
1118 field="variable",
1119 type="Flag",
1120 doc="set if the object has variable brightness",
1121 )
1122 if coordErrDim not in (0, 2, 3):
1123 raise ValueError("coordErrDim={}; must be (0, 2, 3)".format(coordErrDim))
1124 if coordErrDim > 0:
1125 afwTable.CovarianceMatrix2fKey.addFields(
1126 schema=schema,
1127 prefix="coord",
1128 names=["ra", "dec"],
1129 units=["rad", "rad"],
1130 diagonalOnly=(coordErrDim == 2),
1131 )
1133 if addProperMotion or addParallax:
1134 schema.addField(
1135 field="epoch",
1136 type=numpy.float64,
1137 doc="date of observation (TAI, MJD)",
1138 units="day",
1139 )
1141 if addProperMotion:
1142 schema.addField(
1143 field="pm_ra",
1144 type="Angle",
1145 doc="proper motion in the right ascension direction = dra/dt * cos(dec)",
1146 units="rad/year",
1147 )
1148 schema.addField(
1149 field="pm_dec",
1150 type="Angle",
1151 doc="proper motion in the declination direction",
1152 units="rad/year",
1153 )
1154 if properMotionErrDim not in (0, 2, 3):
1155 raise ValueError("properMotionErrDim={}; must be (0, 2, 3)".format(properMotionErrDim))
1156 if properMotionErrDim > 0:
1157 afwTable.CovarianceMatrix2fKey.addFields(
1158 schema=schema,
1159 prefix="pm",
1160 names=["ra", "dec"],
1161 units=["rad/year", "rad/year"],
1162 diagonalOnly=(properMotionErrDim == 2),
1163 )
1164 schema.addField(
1165 field="pm_flag",
1166 type="Flag",
1167 doc="Set if proper motion or proper motion error is bad",
1168 )
1170 if addParallax:
1171 schema.addField(
1172 field="parallax",
1173 type="Angle",
1174 doc="parallax",
1175 units="rad",
1176 )
1177 schema.addField(
1178 field="parallaxErr",
1179 type="Angle",
1180 doc="uncertainty in parallax",
1181 units="rad",
1182 )
1183 schema.addField(
1184 field="parallax_flag",
1185 type="Flag",
1186 doc="Set if parallax or parallax error is bad",
1187 )
1188 return schema
1190 def _calculateCircle(self, bbox, wcs):
1191 """Compute on-sky center and radius of search region.
1193 Parameters
1194 ----------
1195 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
1196 Pixel bounding box.
1197 wcs : `lsst.afw.geom.SkyWcs`
1198 WCS; used to convert pixel positions to sky coordinates.
1200 Returns
1201 -------
1202 results : `lsst.pipe.base.Struct`
1203 A Struct containing:
1205 - coord : `lsst.geom.SpherePoint`
1206 ICRS center of the search region.
1207 - radius : `lsst.geom.Angle`
1208 Radius of the search region.
1209 - bbox : `lsst.geom.Box2D`
1210 Bounding box used to compute the circle.
1211 """
1212 bbox = lsst.geom.Box2D(bbox) # make sure bbox is double and that we have a copy
1213 bbox.grow(self.config.pixelMargin)
1214 coord = wcs.pixelToSky(bbox.getCenter())
1215 radius = max(coord.separation(wcs.pixelToSky(pp)) for pp in bbox.getCorners())
1216 return pipeBase.Struct(coord=coord, radius=radius, bbox=bbox)
1218 def getMetadataBox(self, bbox, wcs, filterName=None, photoCalib=None, epoch=None):
1219 """Return metadata about the load.
1221 This metadata is used for reloading the catalog (e.g., for
1222 reconstituting a normalised match list.
1224 Parameters
1225 ----------
1226 bbox : `lsst.geom.Box2I` or `lsst.geom.Box2D`
1227 Pixel bounding box.
1228 wcs : `lsst.afw.geom.SkyWcs`
1229 WCS; used to convert pixel positions to sky coordinates.
1230 filterName : `str`
1231 Name of camera filter, or `None` or `""` for the default
1232 filter.
1233 photoCalib : `lsst.afw.image.PhotoCalib` (optional)
1234 Calibration, or `None` if unknown.
1235 epoch : `astropy.time.Time` (optional)
1236 Epoch to which to correct proper motion and parallax,
1237 or None to not apply such corrections.
1239 Returns
1240 -------
1241 metadata : lsst.daf.base.PropertyList
1242 Metadata about the load.
1243 """
1244 circle = self._calculateCircle(bbox, wcs)
1245 return self.getMetadataCircle(circle.coord, circle.radius, filterName, photoCalib=photoCalib,
1246 epoch=epoch)
1248 def getMetadataCircle(self, coord, radius, filterName, photoCalib=None, epoch=None):
1249 """Return metadata about the load.
1251 This metadata is used for reloading the catalog (e.g., for
1252 reconstituting a normalised match list.
1254 Parameters
1255 ----------
1256 coord : `lsst.geom.SpherePoint`
1257 ICRS center of the search region.
1258 radius : `lsst.geom.Angle`
1259 Radius of the search region.
1260 filterName : `str`
1261 Name of camera filter, or `None` or `""` for the default
1262 filter.
1263 photoCalib : `lsst.afw.image.PhotoCalib` (optional)
1264 Calibration, or `None` if unknown.
1265 epoch : `astropy.time.Time` (optional)
1266 Epoch to which to correct proper motion and parallax,
1267 or None to not apply such corrections.
1269 Returns
1270 -------
1271 metadata : lsst.daf.base.PropertyList
1272 Metadata about the load
1273 """
1274 md = PropertyList()
1275 md.add('RA', coord.getRa().asDegrees(), 'field center in degrees')
1276 md.add('DEC', coord.getDec().asDegrees(), 'field center in degrees')
1277 md.add('RADIUS', radius.asDegrees(), 'field radius in degrees, minimum')
1278 md.add('SMATCHV', 1, 'SourceMatchVector version number')
1279 filterName = "UNKNOWN" if filterName is None else str(filterName)
1280 md.add('FILTER', filterName, 'filter name for photometric data')
1281 md.add('EPOCH', "NONE" if epoch is None else epoch.mjd, 'Epoch (TAI MJD) for catalog')
1282 return md
1284 def joinMatchListWithCatalog(self, matchCat, sourceCat):
1285 """Relink an unpersisted match list to sources and reference
1286 objects.
1288 A match list is persisted and unpersisted as a catalog of IDs
1289 produced by afw.table.packMatches(), with match metadata
1290 (as returned by the astrometry tasks) in the catalog's metadata
1291 attribute. This method converts such a match catalog into a match
1292 list, with links to source records and reference object records.
1294 Parameters
1295 ----------
1296 matchCat : `lsst.afw.table.BaseCatalog`
1297 Unperisted packed match list.
1298 ``matchCat.table.getMetadata()`` must contain match metadata,
1299 as returned by the astrometry tasks.
1300 sourceCat : `lsst.afw.table.SourceCatalog`
1301 Source catalog. As a side effect, the catalog will be sorted
1302 by ID.
1304 Returns
1305 -------
1306 matchList : `lsst.afw.table.ReferenceMatchVector`
1307 Match list.
1308 """
1309 return joinMatchListWithCatalogImpl(self, matchCat, sourceCat)
1311 def applyProperMotions(self, catalog, epoch):
1312 """Apply proper motion correction to a reference catalog.
1314 Adjust position and position error in the ``catalog``
1315 for proper motion to the specified ``epoch``,
1316 modifying the catalog in place.
1318 Parameters
1319 ----------
1320 catalog : `lsst.afw.table.SimpleCatalog`
1321 Catalog of positions, containing:
1323 - Coordinates, retrieved by the table's coordinate key.
1324 - ``coord_raErr`` : Error in Right Ascension (rad).
1325 - ``coord_decErr`` : Error in Declination (rad).
1326 - ``pm_ra`` : Proper motion in Right Ascension (rad/yr,
1327 East positive)
1328 - ``pm_raErr`` : Error in ``pm_ra`` (rad/yr), optional.
1329 - ``pm_dec`` : Proper motion in Declination (rad/yr,
1330 North positive)
1331 - ``pm_decErr`` : Error in ``pm_dec`` (rad/yr), optional.
1332 - ``epoch`` : Mean epoch of object (an astropy.time.Time)
1333 epoch : `astropy.time.Time`
1334 Epoch to which to correct proper motion,
1335 """
1336 if ("epoch" not in catalog.schema or "pm_ra" not in catalog.schema or "pm_dec" not in catalog.schema):
1337 if self.config.requireProperMotion:
1338 raise RuntimeError("Proper motion correction required but not available from catalog")
1339 self.log.warn("Proper motion correction not available from catalog")
1340 return
1341 applyProperMotionsImpl(self.log, catalog, epoch)
1344def joinMatchListWithCatalogImpl(refObjLoader, matchCat, sourceCat):
1345 """Relink an unpersisted match list to sources and reference
1346 objects.
1348 A match list is persisted and unpersisted as a catalog of IDs
1349 produced by afw.table.packMatches(), with match metadata
1350 (as returned by the astrometry tasks) in the catalog's metadata
1351 attribute. This method converts such a match catalog into a match
1352 list, with links to source records and reference object records.
1354 Parameters
1355 ----------
1356 refObjLoader
1357 Reference object loader to use in getting reference objects
1358 matchCat : `lsst.afw.table.BaseCatalog`
1359 Unperisted packed match list.
1360 ``matchCat.table.getMetadata()`` must contain match metadata,
1361 as returned by the astrometry tasks.
1362 sourceCat : `lsst.afw.table.SourceCatalog`
1363 Source catalog. As a side effect, the catalog will be sorted
1364 by ID.
1366 Returns
1367 -------
1368 matchList : `lsst.afw.table.ReferenceMatchVector`
1369 Match list.
1370 """
1371 matchmeta = matchCat.table.getMetadata()
1372 version = matchmeta.getInt('SMATCHV')
1373 if version != 1:
1374 raise ValueError('SourceMatchVector version number is %i, not 1.' % version)
1375 filterName = matchmeta.getString('FILTER').strip()
1376 try:
1377 epoch = matchmeta.getDouble('EPOCH')
1378 except (pexExcept.NotFoundError, pexExcept.TypeError):
1379 epoch = None # Not present, or not correct type means it's not set
1380 if 'RADIUS' in matchmeta:
1381 # This is a circle style metadata, call loadSkyCircle
1382 ctrCoord = lsst.geom.SpherePoint(matchmeta.getDouble('RA'),
1383 matchmeta.getDouble('DEC'), lsst.geom.degrees)
1384 rad = matchmeta.getDouble('RADIUS') * lsst.geom.degrees
1385 refCat = refObjLoader.loadSkyCircle(ctrCoord, rad, filterName, epoch=epoch).refCat
1386 elif "INNER_UPPER_LEFT_RA" in matchmeta:
1387 # This is the sky box type (only triggers in the LoadReferenceObject class, not task)
1388 # Only the outer box is required to be loaded to get the maximum region, all filtering
1389 # will be done by the unpackMatches function, and no spatial filtering needs to be done
1390 # by the refObjLoader
1391 box = []
1392 for place in ("UPPER_LEFT", "UPPER_RIGHT", "LOWER_LEFT", "LOWER_RIGHT"):
1393 coord = lsst.geom.SpherePoint(matchmeta.getDouble(f"OUTER_{place}_RA"),
1394 matchmeta.getDouble(f"OUTER_{place}_DEC"),
1395 lsst.geom.degrees).getVector()
1396 box.append(coord)
1397 outerBox = sphgeom.ConvexPolygon(box)
1398 refCat = refObjLoader.loadRegion(outerBox, filterName=filterName, epoch=epoch).refCat
1400 refCat.sort()
1401 sourceCat.sort()
1402 return afwTable.unpackMatches(matchCat, refCat, sourceCat)
1405def applyProperMotionsImpl(log, catalog, epoch):
1406 """Apply proper motion correction to a reference catalog.
1408 Adjust position and position error in the ``catalog``
1409 for proper motion to the specified ``epoch``,
1410 modifying the catalog in place.
1412 Parameters
1413 ----------
1414 log : `lsst.log.Log`
1415 Log object to write to.
1416 catalog : `lsst.afw.table.SimpleCatalog`
1417 Catalog of positions, containing:
1419 - Coordinates, retrieved by the table's coordinate key.
1420 - ``coord_raErr`` : Error in Right Ascension (rad).
1421 - ``coord_decErr`` : Error in Declination (rad).
1422 - ``pm_ra`` : Proper motion in Right Ascension (rad/yr,
1423 East positive)
1424 - ``pm_raErr`` : Error in ``pm_ra`` (rad/yr), optional.
1425 - ``pm_dec`` : Proper motion in Declination (rad/yr,
1426 North positive)
1427 - ``pm_decErr`` : Error in ``pm_dec`` (rad/yr), optional.
1428 - ``epoch`` : Mean epoch of object (an astropy.time.Time)
1429 epoch : `astropy.time.Time`
1430 Epoch to which to correct proper motion.
1431 """
1432 if "epoch" not in catalog.schema or "pm_ra" not in catalog.schema or "pm_dec" not in catalog.schema:
1433 log.warn("Proper motion correction not available from catalog")
1434 return
1435 if not catalog.isContiguous():
1436 raise RuntimeError("Catalog must be contiguous")
1437 catEpoch = astropy.time.Time(catalog["epoch"], scale="tai", format="mjd")
1438 log.info("Correcting reference catalog for proper motion to %r", epoch)
1439 # Use `epoch.tai` to make sure the time difference is in TAI
1440 timeDiffsYears = (epoch.tai - catEpoch).to(astropy.units.yr).value
1441 coordKey = catalog.table.getCoordKey()
1442 # Compute the offset of each object due to proper motion
1443 # as components of the arc of a great circle along RA and Dec
1444 pmRaRad = catalog["pm_ra"]
1445 pmDecRad = catalog["pm_dec"]
1446 offsetsRaRad = pmRaRad*timeDiffsYears
1447 offsetsDecRad = pmDecRad*timeDiffsYears
1448 # Compute the corresponding bearing and arc length of each offset
1449 # due to proper motion, and apply the offset
1450 # The factor of 1e6 for computing bearing is intended as
1451 # a reasonable scale for typical values of proper motion
1452 # in order to avoid large errors for small values of proper motion;
1453 # using the offsets is another option, but it can give
1454 # needlessly large errors for short duration
1455 offsetBearingsRad = numpy.arctan2(pmDecRad*1e6, pmRaRad*1e6)
1456 offsetAmountsRad = numpy.hypot(offsetsRaRad, offsetsDecRad)
1457 for record, bearingRad, amountRad in zip(catalog, offsetBearingsRad, offsetAmountsRad):
1458 record.set(coordKey,
1459 record.get(coordKey).offset(bearing=bearingRad*lsst.geom.radians,
1460 amount=amountRad*lsst.geom.radians))
1461 # Increase error in RA and Dec based on error in proper motion
1462 if "coord_raErr" in catalog.schema:
1463 catalog["coord_raErr"] = numpy.hypot(catalog["coord_raErr"],
1464 catalog["pm_raErr"]*timeDiffsYears)
1465 if "coord_decErr" in catalog.schema:
1466 catalog["coord_decErr"] = numpy.hypot(catalog["coord_decErr"],
1467 catalog["pm_decErr"]*timeDiffsYears)