Sample¶

What the Sample object
Working with Sample object in Python

What the Sample object ¶

The sample object holds details of the samples in an experiment. While most of the time this will refer to a single sample, it can describe a collection of samples. Specifically this holds information about a samples.

Material properties and chenmical copmosition
Shape and dimensions
Crystal Structure

Working with Sample object in Python ¶

You can look at the Sample API reference for a full list of properties and operations, but here are some of the key ones.

Getting the Sample Object from a Workspace ¶

ws=CreateWorkspace(DataX='1,2',DataY='1')
s=ws.sample()

Sample Properties ¶

ws = CreateSampleWorkspace("Histogram",NumBanks=1,BankPixelWidth=1)
s = ws.sample()

# Dimensions
s.setHeight(0.1)
s.setWidth(0.2)
s.setThickness(0.3)
print "Height:", s.getHeight()
print "Width:", s.getWidth()
print "Thickness:", s.getThickness()

# Material
SetSampleMaterial(ws,ChemicalFormula="V")
m = s.getMaterial()
print "Material Name", m.name()
print "Total scattering X-Section:", m.totalScatterXSection()

# Crystal Structure
SetUB(ws,a=2,b=3,c=4,alpha=90,beta=90,gamma=90,u="1,0,0",v="0,0,1")
ol=s.getOrientedLattice()
print "Data lattice parameters are:",ol.a(),ol.b(),ol.c(),ol.alpha(),ol.beta(),ol.gamma()

Multiple Samples ¶

The Sample() method actually returns a collection, however if you do not specify which sample you are after you will get he first member of the collection. So

ws = CreateSampleWorkspace("Histogram",NumBanks=1,BankPixelWidth=1)

s = ws.sample()
# Is the same as
s = ws.sample()[0]

# You can ask how many samples there are with
size = ws.sample().size()

Category: Concepts