lsst.afw.geom._python._transform Namespace Reference

Functions
	getJacobian (self, x)
	then (self, next, simplify=True)
	unpickleTransform (cls, state)
	reduceTransform (transform)
	addTransformMethods (cls)

Variables
dict	transformRegistry = {}
	toEndpoint
	getJacobian
	then

Detailed Description

Python helpers for pybind11 wrapping of Transform classes and subclasses

.. _pybind11_transform_classes:

Transform Classes and Subclasses
--------------------------------

Transforms are instances of
lsst::afw::geom::Transform<FromEndpoint, ToEndpoint>
and subclasses, such as lsst::afw::geom::SkyWcs.

In Python the templated Transform classes have names such as
`lsst.afw.geom.TransformSpherePointToPoint2` for
`lsst::afw::geom::Transform<SpherePointEndpoint, Point2Endpoint>`

Function Documentation

addTransformMethods()

lsst.afw.geom._python._transform.addTransformMethods

(

cls

)

Add pure python methods to the specified Transform class, and register
the class in `transformRegistry`

All :ref:`_pybind11_transform_classes` must call this function.

Parameters
----------
cls : :ref:`_pybind11_transform_classes`
A Transform class or subclass, e.g.
`lsst.afw.geom.TransformPoint2ToSpherePoint`

Definition at line 94 of file _transform.py.

def addTransformMethods(cls):
    """Add pure python methods to the specified Transform class, and register
    the class in `transformRegistry`
 
    All :ref:`_pybind11_transform_classes` must call this function.
 
    Parameters
    ----------
    cls : :ref:`_pybind11_transform_classes`
    A Transform class or subclass, e.g.
    `lsst.afw.geom.TransformPoint2ToSpherePoint`
    """
    global transformRegistry
    className = cls.__name__
    if className in transformRegistry:
        raise RuntimeError(f"Class {className!r}={transformRegistry[className]} already registered; "
                           f"cannot register class {cls}")
    transformRegistry[cls.__name__] = cls
    cls.getJacobian = getJacobian
    cls.then = then
    cls.__reduce__ = reduceTransform

getJacobian()

lsst.afw.geom._python._transform.getJacobian	(		self,
			x )

Definition at line 47 of file _transform.py.

def getJacobian(self, x):
    # Force 2D matrix over numpy's protests
    matrix = self._getJacobian(x)
    matrix.shape = (self.toEndpoint.nAxes,
                    self.fromEndpoint.nAxes)
    return matrix
 
 

reduceTransform()

lsst.afw.geom._python._transform.reduceTransform

(

transform

)

Pickle a Transform object

This provides the `__reduce__` implementation for a Transform.

Definition at line 86 of file _transform.py.

def reduceTransform(transform):
    """Pickle a Transform object
 
    This provides the `__reduce__` implementation for a Transform.
    """
    return unpickleTransform, (type(transform), transform.writeString())
 
 

then()

lsst.afw.geom._python._transform.then	(		self,
			next,
			simplify = True )

Concatenate two transforms

The result of A.then(B) is is C(x) = B(A(x))

Definition at line 55 of file _transform.py.

def then(self, next, simplify=True):
    """Concatenate two transforms
 
    The result of A.then(B) is is C(x) = B(A(x))
    """
    if self.toEndpoint == next.fromEndpoint:
        return self._then(next, simplify=simplify)
    else:
        raise lsst.pex.exceptions.InvalidParameterError(
            "Cannot concatenate %r and %r: endpoints do not match."
            % (self, next))
 
 

unpickleTransform()

lsst.afw.geom._python._transform.unpickleTransform	(		cls,
			state )

Unpickle a Transform object

Parameters
----------
cls : `type`
    A `Transform` class.
state : `str`
    Pickled state.

Returns
-------
transform : `cls`
    The unpickled Transform.

Definition at line 68 of file _transform.py.

def unpickleTransform(cls, state):
    """Unpickle a Transform object
 
    Parameters
    ----------
    cls : `type`
        A `Transform` class.
    state : `str`
        Pickled state.
 
    Returns
    -------
    transform : `cls`
        The unpickled Transform.
    """
    return cls.readString(state)
 
 

Variable Documentation

getJacobian

lsst.afw.geom._python._transform.getJacobian

Definition at line 112 of file _transform.py.

then

lsst.afw.geom._python._transform.then

Definition at line 113 of file _transform.py.

toEndpoint

lsst.afw.geom._python._transform.toEndpoint

Definition at line 60 of file _transform.py.

transformRegistry

dict lsst.afw.geom._python._transform.transformRegistry = {}

Definition at line 44 of file _transform.py.