Inheritance diagram for lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper:
Public Member Functions | |
| __init__ (self, pix_to_field, origin=None, world_origin=None) | |
| origin (self) | |
| world_origin (self) | |
Public Attributes | |
| u0 | |
| x0 | |
Protected Member Functions | |
| _xyTouv (self, x, y, color=None) | |
| _uvToxy (self, u, v, color) | |
| _posToWorld (self, image_pos, color=None) | |
| _local (self, image_pos, color=None) | |
| _newOrigin (self, origin, world_origin) | |
Protected Attributes | |
| _pix_to_field | |
| _origin | |
| _world_origin | |
| _mapping | |
| _color | |
| _rad_to_arcsec | |
Static Protected Attributes | |
| float | _rad_to_arcsec = 206264.80624709636 |
Detailed Description
Wrap a `lsst.afw.geom.TransformPoint2ToPoint2[2->2]` in a GalSim WCS.
Parameters
----------
pix_to_field : `lsst.afw.geom.TransformPoint2ToPoint2[2->2]`
Transform to wrap. Most likely PIXELS -> FIELD_ANGLE, but other 2D ->
2D transforms should be possible.
origin : `galsim.PositionD`, optional
Origin in image coordinates.
world_origin : `galsim.PositionD`, optional
Origin in world coordinates.
Notes
-----
GalSim EuclideanWCS assumes
u = ufunc(x-x0, y-y0) + u0
v = vfunc(x-x0, y-y0) + v0
where u,v are world (likely field angles), and (x, y) are pixels.
GalSim also assumes that origin = x0, y0 and world_origin = u0, v0.
I might have naively thought that uv(origin) == world_origin, but
that appears to not be required. So we're just going to leave both
free.
Definition at line 75 of file wcs_wrapper.py.
Constructor & Destructor Documentation
◆ __init__()
| lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper.__init__ | ( | self, | |
| pix_to_field, | |||
| origin = None, | |||
| world_origin = None ) |
Definition at line 102 of file wcs_wrapper.py.
102 def __init__(self, pix_to_field, origin=None, world_origin=None):
103 if origin is None:
104 # Use galsim._PositionD as it's faster than galsim.PositionD
105 origin = galsim._PositionD(0.0, 0.0)
106 if world_origin is None:
107 world_origin = galsim._PositionD(0.0, 0.0)
108 self._pix_to_field = pix_to_field
109 self._origin = origin
110 self._world_origin = world_origin
111 self._mapping = self._pix_to_field.getMapping()
112 self._color = None
113
Member Function Documentation
◆ _local()
|
protected |
Compute local Jacobian WCS.
Parameters
----------
image_pos : galsim.PositionD
Image position at which to compute local WCS.
color : ndarray
Color to use in transformation. Unused currently.
Returns
-------
local : galsim.JacobianWCS
Local linear approximation to WCS.
Definition at line 186 of file wcs_wrapper.py.
186 def _local(self, image_pos, color=None):
187 """Compute local Jacobian WCS.
188
189 Parameters
190 ----------
191 image_pos : galsim.PositionD
192 Image position at which to compute local WCS.
193 color : ndarray
194 Color to use in transformation. Unused currently.
195
196 Returns
197 -------
198 local : galsim.JacobianWCS
199 Local linear approximation to WCS.
200 """
201 x0 = image_pos.x - self.x0
202 y0 = image_pos.y - self.y0
203
204 duvdxy = self._pix_to_field.getJacobian(Point2D(x0, y0))
205 return galsim.JacobianWCS(
206 *(duvdxy.ravel()*self._rad_to_arcsec)
207 )
208
◆ _newOrigin()
|
protected |
Return a new UVWcsWrapper with new origins.
Parameters
----------
origin : `galsim.PositionD`, optional
Origin in image coordinates.
world_origin : `galsim.PositionD`, optional
Origin in world coordinates.
Returns
-------
ret : `UVWcsWrapper`
Transformed WCS.
Definition at line 209 of file wcs_wrapper.py.
209 def _newOrigin(self, origin, world_origin):
210 """Return a new UVWcsWrapper with new origins.
211
212 Parameters
213 ----------
214 origin : `galsim.PositionD`, optional
215 Origin in image coordinates.
216 world_origin : `galsim.PositionD`, optional
217 Origin in world coordinates.
218
219 Returns
220 -------
221 ret : `UVWcsWrapper`
222 Transformed WCS.
223 """
224 return UVWcsWrapper(self._pix_to_field, origin, world_origin)
◆ _posToWorld()
|
protected |
Convert image coordinate to world coordinate.
Parameters
----------
image_pos : galsim.PositionD
Image coordinate.
color : ndarray
Color to use in transformation. Unused currently.
Returns
-------
world_pos : galsim.PositionD
World coordinate.
Definition at line 168 of file wcs_wrapper.py.
168 def _posToWorld(self, image_pos, color=None):
169 """Convert image coordinate to world coordinate.
170
171 Parameters
172 ----------
173 image_pos : galsim.PositionD
174 Image coordinate.
175 color : ndarray
176 Color to use in transformation. Unused currently.
177
178 Returns
179 -------
180 world_pos : galsim.PositionD
181 World coordinate.
182 """
183 # Use galsim._PositionD as it's faster than galsim.PositionD
184 return galsim._PositionD(*self._xyTouv(image_pos.x, image_pos.y, color))
185
◆ _uvToxy()
|
protected |
Convert world coordinates to image coordinates.
Parameters
----------
u, v : ndarray
World coordinates.
color : ndarray
Color to use in transformation. Unused currently.
Returns
-------
x, y : ndarray
Image coordinates.
Definition at line 148 of file wcs_wrapper.py.
148 def _uvToxy(self, u, v, color):
149 """Convert world coordinates to image coordinates.
150
151 Parameters
152 ----------
153 u, v : ndarray
154 World coordinates.
155 color : ndarray
156 Color to use in transformation. Unused currently.
157
158 Returns
159 -------
160 x, y : ndarray
161 Image coordinates.
162 """
163 u = (u - self.u0)/self._rad_to_arcsec
164 v = (v - self.v0)/self._rad_to_arcsec
165 x, y = self._mapping.applyInverse(np.vstack((u, v)))
166 return x + self.x0, y + self.y0
167
◆ _xyTouv()
|
protected |
Convert image coordinates to world coordinates.
Parameters
----------
x, y : ndarray
Image coordinates.
color : ndarray
Color to use in transformation. Unused currently.
Returns
-------
u, v : ndarray
World coordinates.
Definition at line 126 of file wcs_wrapper.py.
126 def _xyTouv(self, x, y, color=None):
127 """Convert image coordinates to world coordinates.
128
129 Parameters
130 ----------
131 x, y : ndarray
132 Image coordinates.
133 color : ndarray
134 Color to use in transformation. Unused currently.
135
136 Returns
137 -------
138 u, v : ndarray
139 World coordinates.
140 """
141 x = x - self.x0
142 y = y - self.y0
143 u, v = self._mapping.applyForward(np.vstack((x, y)))
144 u *= self._rad_to_arcsec
145 v *= self._rad_to_arcsec
146 return u + self.u0, v + self.v0
147
◆ origin()
| lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper.origin | ( | self | ) |
The image coordinate position to use as the origin.
Definition at line 115 of file wcs_wrapper.py.
115 def origin(self):
116 """The image coordinate position to use as the origin.
117 """
118 return self._origin
119
◆ world_origin()
| lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper.world_origin | ( | self | ) |
The world coordinate position to use as the origin.
Definition at line 121 of file wcs_wrapper.py.
121 def world_origin(self):
122 """The world coordinate position to use as the origin.
123 """
124 return self._world_origin
125
Member Data Documentation
◆ _color
|
protected |
Definition at line 112 of file wcs_wrapper.py.
◆ _mapping
|
protected |
Definition at line 111 of file wcs_wrapper.py.
◆ _origin
|
protected |
Definition at line 109 of file wcs_wrapper.py.
◆ _pix_to_field
|
protected |
Definition at line 108 of file wcs_wrapper.py.
◆ _rad_to_arcsec [1/2]
|
staticprotected |
Definition at line 100 of file wcs_wrapper.py.
◆ _rad_to_arcsec [2/2]
|
protected |
Definition at line 206 of file wcs_wrapper.py.
◆ _world_origin
|
protected |
Definition at line 110 of file wcs_wrapper.py.
◆ u0
| lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper.u0 |
Definition at line 146 of file wcs_wrapper.py.
◆ x0
| lsst.meas.extensions.piff.wcs_wrapper.UVWcsWrapper.x0 |
Definition at line 166 of file wcs_wrapper.py.
The documentation for this class was generated from the following file:
- /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/meas_extensions_piff/g64a986408d+21ad69e7e1/python/lsst/meas/extensions/piff/wcs_wrapper.py
