Base class for all position types.

All subclasses must define:

type

a 1-character type identifier for the position.

__init__()

constructor, taking all angle/vector/matrix arguments plus the hardware. Should store all of the recognized arguments as attributes, and complain about others. It should also accept to be called with only a p argument, referring to a position of the same type, and make itself a copy of p.

With(x=y)

a modifier method that returns the position with one or more of the attributes changed. Position should be immutable, so this method must return a copied object!

as_?()

conversion routines for ? in all types (but capitalized) (Currently as_B(), as_C(), as_E(), as_F(), as_G(), as_K(), as_N(), as_X()) including itself. Many of these can be implemented as cascades.

**asType(type=?)

conversion routine that takes the target type as a string parameter.

towards(other,fraction)

interpolation function that takes an other position of the same type, and an interpolation fraction, and that returns a position that can be mathematically expressed as::

self*(1-fraction)+other*fraction

Storable()

return a dictionary with all arguments to the constructor that can be used to reconstruct the position object including the type, but excluding the hardware.

__repr__()

a unique string representation, presentable to the user.

Some methods are specific to specific 'type's of positions:

Alternate()

for kappa and eulerian positions, returns a position with different angles but the same orientation of the crystal on the goniostat.

NegateTheta()

for k positions, returns a position with theta negative that has the same diffraction vector active at the center of the detector.

Xrot(angle)

for g positions, rotates the crystal angle clockwise around the X axis.

Yrot(angle)

for g positions, rotates the crystal angle clockwise around the Y axis.

Zrot(angle)

for g positions, rotates the crystal angle clockwise around the Z axis.

WithHighTwoTheta (
        self,
        ang,
        margin,
        )

WithLowTwoTheta (
        self,
        ang,
        margin=0,
        )

allowed ( self )

asType ( self,  type )

detector_edgetheta (
        self,
        angle,
        margin=0,
        )

detector_edgevec (
        self,
        angle,
        margin=0,
        )

detector_hitrotvec (
        self,
        v,
        margin=0,
        )

detector_hitvec (
        self,
        v,
        margin=0,
        )

detector_twothetaspan ( self,  margin=0 )

goniometermatrix ( self )

orange ( self )

oranges ( self )

rotateBackTwoTheta ( self,  v )

rotateToTwoTheta ( self,  v )