Table of Contents
Set the UB matrix, given either lattice parametersand orientation vectors or the UB matrix elements
Name | Direction | Type | Default | Description |
---|---|---|---|---|
Workspace | InOut | Workspace | Mandatory | An input workspace. |
a | Input | number | 1 | Lattice parameter a |
b | Input | number | 1 | Lattice parameter b |
c | Input | number | 1 | Lattice parameter c |
alpha | Input | number | 90 | Lattice parameter alpha (degrees) |
beta | Input | number | 90 | Lattice parameter beta (degrees) |
gamma | Input | number | 90 | Lattice parameter gamma(degrees) |
u | Input | dbl list | 1,0,0 | Vector along k_i, when goniometer is at 0 |
v | Input | dbl list | 0,1,0 | In plane vector perpendicular to k_i, when goniometer is at 0 |
UB | Input | dbl list | 0,0,0,0,0,0,0,0,0 | UB Matrix |
MDSampleNumber | Input | number | Optional | For an MD workspace, the sample number to wich to attach an oriented lattice (starting from 0). No number, or negative number, means that it will copy to all samples |
The algorithms will attach an OrientedLattice object to a sample in the workspace. For MD workspaces, you can select to which sample to attach it. If nothing entered, it will attach to all. If bad number is enetered, it will attach to first sample.
If UB matrix elements are entered, lattice parameters and orientation vectors are ignored. The algorithm will throw an exception if the determinant is 0. If the UB matrix is all zeros (default), it will calculate it from lattice parameters and orientation vectors (MSlice and Horace style). The algorithm will throw an exception if u and v are collinear, or one of them is very small in magnitude.
# create a workspace (or you can load one)
ws=CreateSingleValuedWorkspace(5)
#set a UB matrix using the vector along k_i as 1,1,0, and the 0,0,1 vector in the horizontal plane
SetUB(ws,a=5,b=6,c=7,alpha=90, beta=90, gamma=90, u="1,1,0", v="0,0,1")
#check that it works
from numpy import *
mat=array(ws.sample().getOrientedLattice().getUB())
print "UB matrix"
print array_str(mat,precision=3, suppress_small=True)
Output:
UB matrix
[[-0. 0. 0.143]
[ 0.128 -0.128 0. ]
[ 0.154 0.107 -0. ]]
Categories: Algorithms | Crystal