LSST Applications  21.0.0-172-gfb10e10a+18fedfabac,22.0.0+297cba6710,22.0.0+80564b0ff1,22.0.0+8d77f4f51a,22.0.0+a28f4c53b1,22.0.0+dcf3732eb2,22.0.1-1-g7d6de66+2a20fdde0d,22.0.1-1-g8e32f31+297cba6710,22.0.1-1-geca5380+7fa3b7d9b6,22.0.1-12-g44dc1dc+2a20fdde0d,22.0.1-15-g6a90155+515f58c32b,22.0.1-16-g9282f48+790f5f2caa,22.0.1-2-g92698f7+dcf3732eb2,22.0.1-2-ga9b0f51+7fa3b7d9b6,22.0.1-2-gd1925c9+bf4f0e694f,22.0.1-24-g1ad7a390+a9625a72a8,22.0.1-25-g5bf6245+3ad8ecd50b,22.0.1-25-gb120d7b+8b5510f75f,22.0.1-27-g97737f7+2a20fdde0d,22.0.1-32-gf62ce7b1+aa4237961e,22.0.1-4-g0b3f228+2a20fdde0d,22.0.1-4-g243d05b+871c1b8305,22.0.1-4-g3a563be+32dcf1063f,22.0.1-4-g44f2e3d+9e4ab0f4fa,22.0.1-42-gca6935d93+ba5e5ca3eb,22.0.1-5-g15c806e+85460ae5f3,22.0.1-5-g58711c4+611d128589,22.0.1-5-g75bb458+99c117b92f,22.0.1-6-g1c63a23+7fa3b7d9b6,22.0.1-6-g50866e6+84ff5a128b,22.0.1-6-g8d3140d+720564cf76,22.0.1-6-gd805d02+cc5644f571,22.0.1-8-ge5750ce+85460ae5f3,master-g6e05de7fdc+babf819c66,master-g99da0e417a+8d77f4f51a,w.2021.48
LSST Data Management Base Package
Public Member Functions | Public Attributes | Static Public Attributes | List of all members
lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask Class Reference
Inheritance diagram for lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask:

Public Member Functions

def __init__ (self, butler=None, refObjLoader=None, **kwargs)
 
def getFgcmReferenceStarsHealpix (self, nside, pixel, filterList, nest=False)
 
def getFgcmReferenceStarsSkyCircle (self, ra, dec, radius, filterList)
 

Public Attributes

 refObjLoader
 

Static Public Attributes

 ConfigClass = FgcmLoadReferenceCatalogConfig
 

Detailed Description

Load multi-band reference objects from a reference catalog.

Parameters
----------
butler: `lsst.daf.persistence.Butler`
   Data butler for reading catalogs

Definition at line 86 of file fgcmLoadReferenceCatalog.py.

Constructor & Destructor Documentation

◆ __init__()

def lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask.__init__ (   self,
  butler = None,
  refObjLoader = None,
**  kwargs 
) 
Construct an FgcmLoadReferenceCatalogTask

Parameters
----------
butler: `lsst.daf.persistence.Buter`
   Data butler for reading catalogs.

Definition at line 98 of file fgcmLoadReferenceCatalog.py.

98  def __init__(self, butler=None, refObjLoader=None, **kwargs):
99  """Construct an FgcmLoadReferenceCatalogTask
100 
101  Parameters
102  ----------
103  butler: `lsst.daf.persistence.Buter`
104  Data butler for reading catalogs.
105  """
106  pipeBase.Task.__init__(self, **kwargs)
107  if refObjLoader is None and butler is not None:
108  self.makeSubtask('refObjLoader', butler=butler)
109  else:
110  self.refObjLoader = refObjLoader
111 
112  self.makeSubtask('referenceSelector')
113  self._fluxFilters = None
114  self._fluxFields = None
115  self._referenceFilter = None
116 

Member Function Documentation

◆ getFgcmReferenceStarsHealpix()

def lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask.getFgcmReferenceStarsHealpix (   self,
  nside,
  pixel,
  filterList,
  nest = False 
) 
Get a reference catalog that overlaps a healpix pixel, using multiple
filters.  In addition, apply colorterms if available.

Return format is a numpy recarray for use with fgcm, with the format:

dtype = ([('ra', `np.float64`),
          ('dec', `np.float64`),
          ('refMag', `np.float32`, len(filterList)),
          ('refMagErr', `np.float32`, len(filterList)])

Reference magnitudes (AB) will be 99 for non-detections.

Parameters
----------
nside: `int`
   Healpix nside of pixel to load
pixel: `int`
   Healpix pixel of pixel to load
filterList: `list`
   list of `str` of camera filter names.
nest: `bool`, optional
   Is the pixel in nest format?  Default is False.

Returns
-------
fgcmRefCat: `np.recarray`

Definition at line 117 of file fgcmLoadReferenceCatalog.py.

117  def getFgcmReferenceStarsHealpix(self, nside, pixel, filterList, nest=False):
118  """
119  Get a reference catalog that overlaps a healpix pixel, using multiple
120  filters. In addition, apply colorterms if available.
121 
122  Return format is a numpy recarray for use with fgcm, with the format:
123 
124  dtype = ([('ra', `np.float64`),
125  ('dec', `np.float64`),
126  ('refMag', `np.float32`, len(filterList)),
127  ('refMagErr', `np.float32`, len(filterList)])
128 
129  Reference magnitudes (AB) will be 99 for non-detections.
130 
131  Parameters
132  ----------
133  nside: `int`
134  Healpix nside of pixel to load
135  pixel: `int`
136  Healpix pixel of pixel to load
137  filterList: `list`
138  list of `str` of camera filter names.
139  nest: `bool`, optional
140  Is the pixel in nest format? Default is False.
141 
142  Returns
143  -------
144  fgcmRefCat: `np.recarray`
145  """
146 
147  # Determine the size of the sky circle to load
148  theta, phi = hp.pix2ang(nside, pixel, nest=nest)
149  center = lsst.geom.SpherePoint(phi * lsst.geom.radians, (np.pi/2. - theta) * lsst.geom.radians)
150 
151  corners = hp.boundaries(nside, pixel, step=1, nest=nest)
152  theta_phi = hp.vec2ang(np.transpose(corners))
153 
154  radius = 0.0 * lsst.geom.radians
155  for ctheta, cphi in zip(*theta_phi):
156  rad = center.separation(lsst.geom.SpherePoint(cphi * lsst.geom.radians,
157  (np.pi/2. - ctheta) * lsst.geom.radians))
158  if (rad > radius):
159  radius = rad
160 
161  # Load the fgcm-format reference catalog
162  fgcmRefCat = self.getFgcmReferenceStarsSkyCircle(center.getRa().asDegrees(),
163  center.getDec().asDegrees(),
164  radius.asDegrees(),
165  filterList)
166  catPix = hp.ang2pix(nside, np.radians(90.0 - fgcmRefCat['dec']),
167  np.radians(fgcmRefCat['ra']), nest=nest)
168 
169  inPix, = np.where(catPix == pixel)
170 
171  return fgcmRefCat[inPix]
172 
lsst::geom::SpherePoint
Point in an unspecified spherical coordinate system.
Definition: SpherePoint.h:57

◆ getFgcmReferenceStarsSkyCircle()

def lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask.getFgcmReferenceStarsSkyCircle (   self,
  ra,
  dec,
  radius,
  filterList 
) 
Get a reference catalog that overlaps a circular sky region, using
multiple filters.  In addition, apply colorterms if available.

Return format is a numpy recarray for use with fgcm.

dtype = ([('ra', `np.float64`),
          ('dec', `np.float64`),
          ('refMag', `np.float32`, len(filterList)),
          ('refMagErr', `np.float32`, len(filterList)])

Reference magnitudes (AB) will be 99 for non-detections.

Parameters
----------
ra: `float`
   ICRS right ascension, degrees.
dec: `float`
   ICRS declination, degrees.
radius: `float`
   Radius to search, degrees.
filterList: `list`
   list of `str` of camera filter names.

Returns
-------
fgcmRefCat: `np.recarray`

Definition at line 173 of file fgcmLoadReferenceCatalog.py.

173  def getFgcmReferenceStarsSkyCircle(self, ra, dec, radius, filterList):
174  """
175  Get a reference catalog that overlaps a circular sky region, using
176  multiple filters. In addition, apply colorterms if available.
177 
178  Return format is a numpy recarray for use with fgcm.
179 
180  dtype = ([('ra', `np.float64`),
181  ('dec', `np.float64`),
182  ('refMag', `np.float32`, len(filterList)),
183  ('refMagErr', `np.float32`, len(filterList)])
184 
185  Reference magnitudes (AB) will be 99 for non-detections.
186 
187  Parameters
188  ----------
189  ra: `float`
190  ICRS right ascension, degrees.
191  dec: `float`
192  ICRS declination, degrees.
193  radius: `float`
194  Radius to search, degrees.
195  filterList: `list`
196  list of `str` of camera filter names.
197 
198  Returns
199  -------
200  fgcmRefCat: `np.recarray`
201  """
202 
203  center = lsst.geom.SpherePoint(ra * lsst.geom.degrees, dec * lsst.geom.degrees)
204 
205  # Check if we haev previously cached values for the fluxFields
206  if self._fluxFilters is None or self._fluxFilters != filterList:
207  self._determine_flux_fields(center, filterList)
208 
209  skyCircle = self.refObjLoader.loadSkyCircle(center,
210  radius * lsst.geom.degrees,
211  self._referenceFilter)
212 
213  if not skyCircle.refCat.isContiguous():
214  refCat = skyCircle.refCat.copy(deep=True)
215  else:
216  refCat = skyCircle.refCat
217 
218  # Select on raw (uncorrected) catalog, where the errors should make more sense
219  goodSources = self.referenceSelector.selectSources(refCat)
220  selected = goodSources.selected
221 
222  fgcmRefCat = np.zeros(np.sum(selected), dtype=[('ra', 'f8'),
223  ('dec', 'f8'),
224  ('refMag', 'f4', len(filterList)),
225  ('refMagErr', 'f4', len(filterList))])
226  if fgcmRefCat.size == 0:
227  # Return an empty catalog if we don't have any selected sources
228  return fgcmRefCat
229 
230  # The ra/dec native Angle format is radians
231  # We determine the conversion from the native units (typically
232  # radians) to degrees for the first observation. This allows us
233  # to treate ra/dec as numpy arrays rather than Angles, which would
234  # be approximately 600x slower.
235 
236  conv = refCat[0]['coord_ra'].asDegrees() / float(refCat[0]['coord_ra'])
237  fgcmRefCat['ra'] = refCat['coord_ra'][selected] * conv
238  fgcmRefCat['dec'] = refCat['coord_dec'][selected] * conv
239 
240  # Default (unset) values are 99.0
241  fgcmRefCat['refMag'][:, :] = 99.0
242  fgcmRefCat['refMagErr'][:, :] = 99.0
243 
244  if self.config.applyColorTerms:
245  if isinstance(self.refObjLoader, ReferenceObjectLoader):
246  # Gen3
247  refCatName = self.refObjLoader.config.value.ref_dataset_name
248  else:
249  # Gen2
250  refCatName = self.refObjLoader.ref_dataset_name
251 
252  for i, (filterName, fluxField) in enumerate(zip(self._fluxFilters, self._fluxFields)):
253  if fluxField is None:
254  continue
255 
256  self.log.debug("Applying color terms for filtername=%r" % (filterName))
257 
258  colorterm = self.config.colorterms.getColorterm(filterName, refCatName, doRaise=True)
259 
260  refMag, refMagErr = colorterm.getCorrectedMagnitudes(refCat)
261 
262  # nan_to_num replaces nans with zeros, and this ensures that we select
263  # magnitudes that both filter out nans and are not very large (corresponding
264  # to very small fluxes), as "99" is a common sentinel for illegal magnitudes.
265 
266  good, = np.where((np.nan_to_num(refMag[selected]) < 90.0)
267  & (np.nan_to_num(refMagErr[selected]) < 90.0)
268  & (np.nan_to_num(refMagErr[selected]) > 0.0))
269 
270  fgcmRefCat['refMag'][good, i] = refMag[selected][good]
271  fgcmRefCat['refMagErr'][good, i] = refMagErr[selected][good]
272 
273  else:
274  # No colorterms
275 
276  for i, (filterName, fluxField) in enumerate(zip(self._fluxFilters, self._fluxFields)):
277  # nan_to_num replaces nans with zeros, and this ensures that we select
278  # fluxes that both filter out nans and are positive.
279  good, = np.where((np.nan_to_num(refCat[fluxField][selected]) > 0.0)
280  & (np.nan_to_num(refCat[fluxField+'Err'][selected]) > 0.0))
281  refMag = (refCat[fluxField][selected][good] * units.nJy).to_value(units.ABmag)
282  refMagErr = abMagErrFromFluxErr(refCat[fluxField+'Err'][selected][good],
283  refCat[fluxField][selected][good])
284  fgcmRefCat['refMag'][good, i] = refMag
285  fgcmRefCat['refMagErr'][good, i] = refMagErr
286 
287  return fgcmRefCat
288 
lsst::afw::image::abMagErrFromFluxErr
double abMagErrFromFluxErr(double fluxErr, double flux)
Compute AB magnitude error from flux and flux error in Janskys.
Definition: Calib.h:52

Member Data Documentation

◆ ConfigClass

lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask.ConfigClass = FgcmLoadReferenceCatalogConfig
static

Definition at line 95 of file fgcmLoadReferenceCatalog.py.

◆ refObjLoader

lsst.fgcmcal.fgcmLoadReferenceCatalog.FgcmLoadReferenceCatalogTask.refObjLoader

Definition at line 110 of file fgcmLoadReferenceCatalog.py.

The documentation for this class was generated from the following file:
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