Inheritance diagram for lsst.skymap.tractInfo.TractInfo:
Public Member Functions | |
| __init__ (self, id, tractBuilder, ctrCoord, vertexCoordList, tractOverlap, wcs, innerBoxCorners=None) | |
| getSequentialPatchIndex (self, patchInfo) | |
| getSequentialPatchIndexFromPair (self, index) | |
| getPatchIndexPair (self, sequentialIndex) | |
| findPatch (self, coord) | |
| findPatchList (self, coordList) | |
| getBBox (self) | |
| getCtrCoord (self) | |
| getId (self) | |
| getNumPatches (self) | |
| getPatchBorder (self) | |
| getPatchInfo (self, index) | |
| getPatchInnerDimensions (self) | |
| getTractOverlap (self) | |
| getVertexList (self) | |
| getInnerSkyPolygon (self) | |
| getInnerSkyRegion (self) | |
| getOuterSkyPolygon (self) | |
| getWcs (self) | |
| __str__ (self) | |
| __repr__ (self) | |
| __iter__ (self) | |
| __len__ (self) | |
| __getitem__ (self, index) | |
| contains (self, coord) | |
Protected Member Functions | |
| _minimumBoundingBox (self, wcs) | |
| _finalOrientation (self, bbox, wcs) | |
Protected Attributes | |
| _id | |
| _ctrCoord | |
| _vertexCoordList | |
| _tractOverlap | |
| _tractBuilder | |
| _innerBoxCorners | |
| _numPatches | |
| _bbox | |
| _wcs | |
Properties | |
| bbox = property(getBBox) | |
| ctr_coord = property(getCtrCoord) | |
| tract_id = property(getId) | |
| num_patches = property(getNumPatches) | |
| patch_border = property(getPatchBorder) | |
| patch_inner_dimensions = property(getPatchInnerDimensions) | |
| tract_overlap = property(getTractOverlap) | |
| vertex_list = property(getVertexList) | |
| inner_sky_polygon = property(getInnerSkyPolygon) | |
| inner_sky_region = property(getInnerSkyRegion) | |
| outer_sky_polygon = property(getOuterSkyPolygon) | |
| wcs = property(getWcs) | |
Detailed Description
Information about a tract in a SkyMap sky pixelization
Parameters
----------
id : `int`
tract ID
tractBuilder : Subclass of `lsst.skymap.BaseTractBuilder`
Object used to compute patch geometry.
ctrCoord : `lsst.geom.SpherePoint`
ICRS sky coordinate of center of inner region of tract; also used as
the CRVAL for the WCS.
vertexCoordList : `list` of `lsst.geom.SpherePoint`
Vertices that define the boundaries of the inner region.
tractOverlap : `lsst.geom.Angle`
Minimum overlap between adjacent sky tracts; this defines the minimum
distance the tract extends beyond the inner region in all directions.
wcs : `lsst.afw.image.SkyWcs`
WCS for tract. The reference pixel will be shifted as required so that
the lower left-hand pixel (index 0,0) has pixel position 0.0, 0.0.
innerBoxCorners : `list` [`lsst.sphgeom.LonLat`], optional
If set then the ``inner_sky_region`` will be a `lsst.sphgeom.Box` with
these corners as opposed to a `lsst.sphgeom.ConvexPolygon` built from
the ``vertex_list``.
Notes
-----
The tract is subdivided into rectangular patches. Each patch has the
following properties:
- An inner region defined by an inner bounding box. The inner regions of
the patches exactly tile the tract, and all inner regions have the same
dimensions. The tract is made larger as required to make this work.
- An outer region defined by an outer bounding box. The outer region
extends beyond the inner region by patchBorder pixels in all directions,
except there is no border at the edges of the tract.
Thus patches overlap each other but never extend off the tract.
If you do not want any overlap between adjacent patches then set
patchBorder to 0.
- An index that consists of a pair of integers:
* 0 <= x index < numPatches[0]
* 0 <= y index < numPatches[1]
Patch 0,0 is at the minimum corner of the tract bounding box.
- It is not enforced that ctrCoord is the center of vertexCoordList, but
SkyMap relies on it.
Definition at line 35 of file tractInfo.py.
Constructor & Destructor Documentation
◆ __init__()
| lsst.skymap.tractInfo.TractInfo.__init__ | ( | self, | |
| id, | |||
| tractBuilder, | |||
| ctrCoord, | |||
| vertexCoordList, | |||
| tractOverlap, | |||
| wcs, | |||
| innerBoxCorners = None ) |
Reimplemented in lsst.skymap.tractInfo.ExplicitTractInfo, and lsst.skymap.healpixSkyMap.HealpixTractInfo.
Definition at line 87 of file tractInfo.py.
87 def __init__(self, id, tractBuilder, ctrCoord, vertexCoordList, tractOverlap, wcs, innerBoxCorners=None):
88 self._id = id
89 self._ctrCoord = ctrCoord
90 self._vertexCoordList = tuple(vertexCoordList)
91 self._tractOverlap = tractOverlap
92 self._tractBuilder = tractBuilder
93 self._innerBoxCorners = innerBoxCorners
94
95 minBBox = self._minimumBoundingBox(wcs)
96 initialBBox, self._numPatches = self._tractBuilder.setupPatches(minBBox, wcs)
97 self._bbox, self._wcs = self._finalOrientation(initialBBox, wcs)
98
Member Function Documentation
◆ __getitem__()
| lsst.skymap.tractInfo.TractInfo.__getitem__ | ( | self, | |
| index ) |
Definition at line 415 of file tractInfo.py.
415 def __getitem__(self, index):
416 return self.getPatchInfo(index)
417
◆ __iter__()
| lsst.skymap.tractInfo.TractInfo.__iter__ | ( | self | ) |
Definition at line 405 of file tractInfo.py.
405 def __iter__(self):
406 xNum, yNum = self.getNumPatches()
407 for y in range(yNum):
408 for x in range(xNum):
409 yield self.getPatchInfo(Index2D(x=x, y=y))
410
◆ __len__()
| lsst.skymap.tractInfo.TractInfo.__len__ | ( | self | ) |
Definition at line 411 of file tractInfo.py.
411 def __len__(self):
412 xNum, yNum = self.getNumPatches()
413 return xNum*yNum
414
◆ __repr__()
| lsst.skymap.tractInfo.TractInfo.__repr__ | ( | self | ) |
Definition at line 402 of file tractInfo.py.
402 def __repr__(self):
403 return "TractInfo(id=%s, ctrCoord=%s)" % (self._id, self._ctrCoord.getVector())
404
◆ __str__()
| lsst.skymap.tractInfo.TractInfo.__str__ | ( | self | ) |
Definition at line 399 of file tractInfo.py.
399 def __str__(self):
400 return "TractInfo(id=%s)" % (self._id,)
401
◆ _finalOrientation()
|
protected |
Determine the final orientation
We offset everything so the lower-left corner is at 0,0
and compute the final Wcs.
Parameters
----------
bbox : `lsst.geom.Box2I`
Current bounding box.
wcs : `lsst.afw.geom.SkyWcs
Current Wcs.
Returns
-------
finalBBox : `lsst.geom.Box2I`
Revised bounding box.
wcs : `lsst.afw.geom.SkyWcs`
Revised Wcs.
Definition at line 123 of file tractInfo.py.
123 def _finalOrientation(self, bbox, wcs):
124 """Determine the final orientation
125
126 We offset everything so the lower-left corner is at 0,0
127 and compute the final Wcs.
128
129 Parameters
130 ----------
131 bbox : `lsst.geom.Box2I`
132 Current bounding box.
133 wcs : `lsst.afw.geom.SkyWcs
134 Current Wcs.
135
136 Returns
137 -------
138 finalBBox : `lsst.geom.Box2I`
139 Revised bounding box.
140 wcs : `lsst.afw.geom.SkyWcs`
141 Revised Wcs.
142 """
144 # shift the WCS by the same amount as the bbox; extra code is required
145 # because simply subtracting makes an Extent2I
146 pixPosOffset = geom.Extent2D(finalBBox.getMinX() - bbox.getMinX(),
147 finalBBox.getMinY() - bbox.getMinY())
148 wcs = wcs.copyAtShiftedPixelOrigin(pixPosOffset)
149 return finalBBox, wcs
150
◆ _minimumBoundingBox()
|
protected |
Calculate the minimum bounding box for the tract, given the WCS. The bounding box is created in the frame of the supplied WCS, so that it's OK if the coordinates are negative. We compute the bounding box that holds all the vertices and the desired overlap.
Reimplemented in lsst.skymap.tractInfo.ExplicitTractInfo.
Definition at line 99 of file tractInfo.py.
99 def _minimumBoundingBox(self, wcs):
100 """Calculate the minimum bounding box for the tract, given the WCS.
101
102 The bounding box is created in the frame of the supplied WCS,
103 so that it's OK if the coordinates are negative.
104
105 We compute the bounding box that holds all the vertices and the
106 desired overlap.
107 """
108 minBBoxD = geom.Box2D()
109 halfOverlap = self._tractOverlap / 2.0
110 for vertexCoord in self._vertexCoordList:
111 if self._tractOverlap == 0:
112 minBBoxD.include(wcs.skyToPixel(vertexCoord))
113 else:
114 numAngles = 24
115 angleIncr = geom.Angle(360.0, geom.degrees) / float(numAngles)
116 for i in range(numAngles):
117 offAngle = angleIncr * i
118 offCoord = vertexCoord.offset(offAngle, halfOverlap)
119 pixPos = wcs.skyToPixel(offCoord)
120 minBBoxD.include(pixPos)
121 return minBBoxD
122
◆ contains()
| lsst.skymap.tractInfo.TractInfo.contains | ( | self, | |
| coord ) |
Does this tract contain the coordinate?
Definition at line 418 of file tractInfo.py.
418 def contains(self, coord):
419 """Does this tract contain the coordinate?"""
420 try:
421 pixel = self.getWcs().skyToPixel(coord)
423 # Point must be way off the tract
424 return False
425 if not np.isfinite(pixel.getX()) or not np.isfinite(pixel.getY()):
426 # Point is definitely off the tract
427 return False
429
430
Reports arguments outside the domain of an operation.
Definition Runtime.h:57
Reports errors that are due to events beyond the control of the program.
Definition Runtime.h:104
◆ findPatch()
| lsst.skymap.tractInfo.TractInfo.findPatch | ( | self, | |
| coord ) |
Find the patch containing the specified coord.
Parameters
----------
coord : `lsst.geom.SpherePoint`
ICRS sky coordinate to search for.
Returns
-------
result : `lsst.skymap.PatchInfo`
PatchInfo of patch whose inner bbox contains the specified coord
Raises
------
LookupError
Raised if coord is not in tract or we cannot determine the
pixel coordinate (which likely means the coord is off the tract).
Definition at line 192 of file tractInfo.py.
192 def findPatch(self, coord):
193 """Find the patch containing the specified coord.
194
195 Parameters
196 ----------
197 coord : `lsst.geom.SpherePoint`
198 ICRS sky coordinate to search for.
199
200 Returns
201 -------
202 result : `lsst.skymap.PatchInfo`
203 PatchInfo of patch whose inner bbox contains the specified coord
204
205 Raises
206 ------
207 LookupError
208 Raised if coord is not in tract or we cannot determine the
209 pixel coordinate (which likely means the coord is off the tract).
210 """
211 try:
212 pixel = self.wcs.skyToPixel(coord)
214 # Point must be way off the tract
215 raise LookupError("Unable to determine pixel position for coordinate %s" % (coord,))
216 pixelInd = geom.Point2I(pixel)
217 if not self._bbox.contains(pixelInd):
218 raise LookupError("coord %s is not in tract %s" % (coord, self.tract_id))
219 # This should probably be the same as above because we only
220 # care about the INNER dimensions.
221 patchInd = tuple(int(pixelInd[i]/self.patch_inner_dimensions[i]) for i in range(2))
222 return self.getPatchInfo(patchInd)
223
◆ findPatchList()
| lsst.skymap.tractInfo.TractInfo.findPatchList | ( | self, | |
| coordList ) |
Find patches containing the specified list of coords.
Parameters
----------
coordList : `list` of `lsst.geom.SpherePoint`
ICRS sky coordinates to search for.
Returns
-------
result : `list` of `lsst.skymap.PatchInfo`
List of PatchInfo for patches that contain, or may contain, the
specified region. The list will be empty if there is no overlap.
Notes
-----
**Warning:**
- This may give incorrect answers on regions that are larger than a
tract.
- This uses a naive algorithm that may find some patches that do not
overlap the region (especially if the region is not a rectangle
aligned along patch x,y).
Definition at line 224 of file tractInfo.py.
224 def findPatchList(self, coordList):
225 """Find patches containing the specified list of coords.
226
227 Parameters
228 ----------
229 coordList : `list` of `lsst.geom.SpherePoint`
230 ICRS sky coordinates to search for.
231
232 Returns
233 -------
234 result : `list` of `lsst.skymap.PatchInfo`
235 List of PatchInfo for patches that contain, or may contain, the
236 specified region. The list will be empty if there is no overlap.
237
238 Notes
239 -----
240 **Warning:**
241
242 - This may give incorrect answers on regions that are larger than a
243 tract.
244
245 - This uses a naive algorithm that may find some patches that do not
246 overlap the region (especially if the region is not a rectangle
247 aligned along patch x,y).
248 """
249 box2D = geom.Box2D()
250 for coord in coordList:
251 try:
252 pixelPos = self.wcs.skyToPixel(coord)
254 # The point is so far off the tract that its pixel position
255 # cannot be computed.
256 continue
257 box2D.include(pixelPos)
258 bbox = geom.Box2I(box2D)
259 bbox.grow(self.getPatchBorder())
260 bbox.clip(self._bbox)
261 if bbox.isEmpty():
262 return ()
263
264 llPatchInd = tuple(int(bbox.getMin()[i]/self.patch_inner_dimensions[i]) for i in range(2))
265 urPatchInd = tuple(int(bbox.getMax()[i]/self.patch_inner_dimensions[i]) for i in range(2))
266 return tuple(self.getPatchInfo((xInd, yInd))
267 for xInd in range(llPatchInd[0], urPatchInd[0]+1)
268 for yInd in range(llPatchInd[1], urPatchInd[1]+1))
269
◆ getBBox()
| lsst.skymap.tractInfo.TractInfo.getBBox | ( | self | ) |
Get bounding box of tract (as an geom.Box2I)
Definition at line 270 of file tractInfo.py.
270 def getBBox(self):
271 """Get bounding box of tract (as an geom.Box2I)
272 """
274
◆ getCtrCoord()
| lsst.skymap.tractInfo.TractInfo.getCtrCoord | ( | self | ) |
Get ICRS sky coordinate of center of tract (as an lsst.geom.SpherePoint)
Definition at line 277 of file tractInfo.py.
277 def getCtrCoord(self):
278 """Get ICRS sky coordinate of center of tract
279 (as an lsst.geom.SpherePoint)
280 """
281 return self._ctrCoord
282
◆ getId()
| lsst.skymap.tractInfo.TractInfo.getId | ( | self | ) |
Get ID of tract
Definition at line 285 of file tractInfo.py.
285 def getId(self):
286 """Get ID of tract
287 """
288 return self._id
289
◆ getInnerSkyPolygon()
| lsst.skymap.tractInfo.TractInfo.getInnerSkyPolygon | ( | self | ) |
Get inner on-sky region as a sphgeom.ConvexPolygon.
Definition at line 361 of file tractInfo.py.
361 def getInnerSkyPolygon(self):
362 """Get inner on-sky region as a sphgeom.ConvexPolygon.
363 """
364 skyUnitVectors = [sp.getVector() for sp in self.getVertexList()]
365 return ConvexPolygon.convexHull(skyUnitVectors)
366
◆ getInnerSkyRegion()
| lsst.skymap.tractInfo.TractInfo.getInnerSkyRegion | ( | self | ) |
Get inner on-sky region.
Definition at line 369 of file tractInfo.py.
369 def getInnerSkyRegion(self):
370 """Get inner on-sky region.
371 """
372 if self._innerBoxCorners:
373 return Box(point1=self._innerBoxCorners[0], point2=self._innerBoxCorners[1])
374 else:
375 skyUnitVectors = [sp.getVector() for sp in self.getVertexList()]
376 return ConvexPolygon.convexHull(skyUnitVectors)
377
◆ getNumPatches()
| lsst.skymap.tractInfo.TractInfo.getNumPatches | ( | self | ) |
Get the number of patches in x, y.
Returns
-------
result : `lsst.skymap.Index2D`
The number of patches in x, y
Definition at line 292 of file tractInfo.py.
292 def getNumPatches(self):
293 """Get the number of patches in x, y.
294
295 Returns
296 -------
297 result : `lsst.skymap.Index2D`
298 The number of patches in x, y
299 """
300 return self._numPatches
301
◆ getOuterSkyPolygon()
| lsst.skymap.tractInfo.TractInfo.getOuterSkyPolygon | ( | self | ) |
Get outer on-sky region as a sphgeom.ConvexPolygon
Definition at line 380 of file tractInfo.py.
380 def getOuterSkyPolygon(self):
381 """Get outer on-sky region as a sphgeom.ConvexPolygon
382 """
383 return makeSkyPolygonFromBBox(bbox=self.getBBox(), wcs=self.getWcs())
384
◆ getPatchBorder()
| lsst.skymap.tractInfo.TractInfo.getPatchBorder | ( | self | ) |
Definition at line 304 of file tractInfo.py.
304 def getPatchBorder(self):
305 return self._tractBuilder.getPatchBorder()
306
◆ getPatchIndexPair()
| lsst.skymap.tractInfo.TractInfo.getPatchIndexPair | ( | self, | |
| sequentialIndex ) |
Convert sequential index into patch index (x,y) pair. Parameters ---------- sequentialIndex : `int` Returns ------- x, y : `lsst.skymap.Index2D`
Definition at line 179 of file tractInfo.py.
179 def getPatchIndexPair(self, sequentialIndex):
180 """Convert sequential index into patch index (x,y) pair.
181
182 Parameters
183 ----------
184 sequentialIndex : `int`
185
186 Returns
187 -------
188 x, y : `lsst.skymap.Index2D`
189 """
190 return self._tractBuilder.getPatchIndexPair(sequentialIndex)
191
◆ getPatchInfo()
| lsst.skymap.tractInfo.TractInfo.getPatchInfo | ( | self, | |
| index ) |
Return information for the specified patch.
Parameters
----------
index : `typing.NamedTuple` ['x': `int`, 'y': `int`]
Index of patch, as a pair of ints;
or a sequential index as returned by getSequentialPatchIndex;
negative values are not supported.
Returns
-------
result : `lsst.skymap.PatchInfo`
The patch info for that index.
Raises
------
IndexError
Raised if index is out of range.
Definition at line 309 of file tractInfo.py.
309 def getPatchInfo(self, index):
310 """Return information for the specified patch.
311
312 Parameters
313 ----------
314 index : `typing.NamedTuple` ['x': `int`, 'y': `int`]
315 Index of patch, as a pair of ints;
316 or a sequential index as returned by getSequentialPatchIndex;
317 negative values are not supported.
318
319 Returns
320 -------
321 result : `lsst.skymap.PatchInfo`
322 The patch info for that index.
323
324 Raises
325 ------
326 IndexError
327 Raised if index is out of range.
328 """
329 return self._tractBuilder.getPatchInfo(index, self._wcs)
330
◆ getPatchInnerDimensions()
| lsst.skymap.tractInfo.TractInfo.getPatchInnerDimensions | ( | self | ) |
Get dimensions of inner region of the patches (all are the same)
Definition at line 331 of file tractInfo.py.
331 def getPatchInnerDimensions(self):
332 """Get dimensions of inner region of the patches (all are the same)
333 """
334 return self._tractBuilder.getPatchInnerDimensions()
335
◆ getSequentialPatchIndex()
| lsst.skymap.tractInfo.TractInfo.getSequentialPatchIndex | ( | self, | |
| patchInfo ) |
Return a single integer that uniquely identifies the given patch within this tract. Parameters ---------- patchInfo : `lsst.skymap.PatchInfo` Returns ------- sequentialIndex : `int`
Definition at line 151 of file tractInfo.py.
151 def getSequentialPatchIndex(self, patchInfo):
152 """Return a single integer that uniquely identifies
153 the given patch within this tract.
154
155 Parameters
156 ----------
157 patchInfo : `lsst.skymap.PatchInfo`
158
159 Returns
160 -------
161 sequentialIndex : `int`
162 """
163 return self._tractBuilder.getSequentialPatchIndex(patchInfo)
164
◆ getSequentialPatchIndexFromPair()
| lsst.skymap.tractInfo.TractInfo.getSequentialPatchIndexFromPair | ( | self, | |
| index ) |
Return a single integer that uniquely identifies the patch index within the tract. Parameters ---------- index : `lsst.skymap.Index2D` Returns ------- sequentialIndex : `int`
Definition at line 165 of file tractInfo.py.
165 def getSequentialPatchIndexFromPair(self, index):
166 """Return a single integer that uniquely identifies
167 the patch index within the tract.
168
169 Parameters
170 ----------
171 index : `lsst.skymap.Index2D`
172
173 Returns
174 -------
175 sequentialIndex : `int`
176 """
177 return self._tractBuilder.getSequentialPatchIndexFromPair(index)
178
◆ getTractOverlap()
| lsst.skymap.tractInfo.TractInfo.getTractOverlap | ( | self | ) |
Get minimum overlap of adjacent sky tracts.
Definition at line 338 of file tractInfo.py.
338 def getTractOverlap(self):
339 """Get minimum overlap of adjacent sky tracts.
340 """
341 return self._tractOverlap
342
◆ getVertexList()
| lsst.skymap.tractInfo.TractInfo.getVertexList | ( | self | ) |
Get list of ICRS sky coordinates of vertices that define the boundary of the inner region. Notes ----- **warning:** this is not a deep copy.
Definition at line 345 of file tractInfo.py.
345 def getVertexList(self):
346 """Get list of ICRS sky coordinates of vertices that define the
347 boundary of the inner region.
348
349 Notes
350 -----
351 **warning:** this is not a deep copy.
352 """
353 return self._vertexCoordList
354
◆ getWcs()
| lsst.skymap.tractInfo.TractInfo.getWcs | ( | self | ) |
Get WCS of tract.
Returns
-------
wcs : `lsst.afw.geom.SkyWcs`
The WCS of this tract
Definition at line 387 of file tractInfo.py.
387 def getWcs(self):
388 """Get WCS of tract.
389
390 Returns
391 -------
392 wcs : `lsst.afw.geom.SkyWcs`
393 The WCS of this tract
394 """
395 return self._wcs
396
Member Data Documentation
◆ _bbox
|
protected |
Definition at line 97 of file tractInfo.py.
◆ _ctrCoord
|
protected |
Definition at line 89 of file tractInfo.py.
◆ _id
|
protected |
Definition at line 88 of file tractInfo.py.
◆ _innerBoxCorners
|
protected |
Definition at line 93 of file tractInfo.py.
◆ _numPatches
|
protected |
Definition at line 96 of file tractInfo.py.
◆ _tractBuilder
|
protected |
Definition at line 92 of file tractInfo.py.
◆ _tractOverlap
|
protected |
Definition at line 91 of file tractInfo.py.
◆ _vertexCoordList
|
protected |
Definition at line 90 of file tractInfo.py.
◆ _wcs
|
protected |
Definition at line 97 of file tractInfo.py.
Property Documentation
◆ bbox
|
static |
Definition at line 275 of file tractInfo.py.
◆ ctr_coord
|
static |
Definition at line 283 of file tractInfo.py.
◆ inner_sky_polygon
|
static |
Definition at line 367 of file tractInfo.py.
◆ inner_sky_region
|
static |
Definition at line 378 of file tractInfo.py.
◆ num_patches
|
static |
Definition at line 302 of file tractInfo.py.
◆ outer_sky_polygon
|
static |
Definition at line 385 of file tractInfo.py.
◆ patch_border
|
static |
Definition at line 307 of file tractInfo.py.
◆ patch_inner_dimensions
|
static |
Definition at line 336 of file tractInfo.py.
◆ tract_id
|
static |
Definition at line 290 of file tractInfo.py.
◆ tract_overlap
|
static |
Definition at line 343 of file tractInfo.py.
◆ vertex_list
|
static |
Definition at line 355 of file tractInfo.py.
◆ wcs
|
static |
Definition at line 397 of file tractInfo.py.
The documentation for this class was generated from the following file:
- /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/skymap/g80478fca09+f29c5d6c70/python/lsst/skymap/tractInfo.py
