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PredictSatellitePeaks v1¶

Summary ¶

The offsets can be from hkl values in a range of hkl values or from peaks in the input PeaksWorkspace

Properties ¶

Name	Direction	Type	Default	Description
Peaks	Input	IPeaksWorkspace	Mandatory	Workspace of Peaks with orientation matrix that indexed the peaks and instrument loaded
SatellitePeaks	Output	IPeaksWorkspace	Mandatory	Workspace of Peaks with peaks with fractional h,k, and/or l values
ModVector1	Input	dbl list	0,0,0	Modulation Vector 1: dh, dk, dl
ModVector2	Input	dbl list	0,0,0	Modulation Vector 2: dh, dk, dl
ModVector3	Input	dbl list	0,0,0	Modulation Vector 3: dh, dk, dl
MaxOrder	Input	number	0	Maximum order to apply Modulation Vectors. Default = 0
CrossTerms	Input	boolean	False	Include combinations of modulation vectors in satellite search
GetModVectorsFromUB	Input	boolean	False	If false Modulation Vectors will be read from input
IncludeIntegerHKL	Input	boolean	True	If false order 0 peaks are not included in workspace (integer HKL)
IncludeAllPeaksInRange	Input	boolean	False	If false only offsets from peaks from Peaks workspace in input are used
WavelengthMin	Input	number	0.1	Minimum wavelength limit at which to start looking for single-crystal peaks.
WavelengthMax	Input	number	100	Maximum wavelength limit at which to start looking for single-crystal peaks.
MinDSpacing	Input	number	0.1	Minimum d-spacing of peaks to consider. Default = 0.1
MaxDSpacing	Input	number	100	Maximum d-spacing of peaks to consider

Description ¶

This Algorithm creates a PeaksWorkspace with peaks occurring at specific fractional offsets from h,k,or l values.

There are options to create Peaks offset from peaks from the input PeaksWorkspace, or to create peaks offset from h,k, and l values in a range. Zero offsets are allowed if some or all integer h,k, or l values are desired. The order can be 1 for +/-1 or 2 for +/-1 and +/-2, etc.

The input PeaksWorkspace must contain an orientation matrix and have been INDEXED by THIS MATRIX when the new peaks are not created from a range of h ,k, and l values

Convention: if includePeaksInRange = true, each new discovered peak’s goniometer matrix will be the goniometer orientation matrix from the PeaksWorkspace. Each new discovered peak’s run number will be the run number from the PeaksWorkspace.

If includePeaksInRange = false, each new discovered peak’s goniometer matrix and run number will be set to the same values as that of the peak it was discovered to be a satellite of.

Usage ¶

Example:

peaks = LoadIsawPeaks("TOPAZ_3007.peaks")
LoadIsawUB(peaks,"TOPAZ_3007.mat")
IndexPeaks(peaks)

fractional_peaks = PredictSatellitePeaks(peaks, ModVector1=[-0.5,0,0.0], MaxOrder=1)
print("Number of fractional peaks: {}".format(fractional_peaks.getNumberPeaks()))