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Diffraction Changes¶

Table of Contents

Powder Diffraction ¶

New algorithm SaveSampleEnvironmentAndShape to save out a sample shape and environment as a single STL file, this can be used to save out pieces with a set rotation or scale, or to assemble multiple stl files into one for viewing purposes.

The Gem scripts can now be used to automatically generate a .cal file, similar to pearl. They can also adjust a parameter file passed in using the argument “calibration_to_adjust”.
Added two new options to the HRPD scripts do_solid_angle_corrections and subtract_empty_instrument allowing setting whether or not these actions should take place.
The Polaris scripts can now detect the chopper mode if none is provided using the frequency block logs.
The Pearl scripts now automatically disable attenuation on long-mode.
The Pearl scripts now set now use a spline coefficient of 5 on long-mode due to the increased amount of noise.
The Pearl scripts now crop to a dspacing of 8 on long-mode to avoid negative values caused by noise after this point.
New example mapping files for GEM and POLARIS have been added to the ISIS powder scripts.
SNSPowderReduction has a new property, OffsetData, which adds a constant to the data at the very end of the reduction.
BASISPowderDiffraction has a new property, RemoveTemp, which allows the user to inspect temporary workspaces is left unchecked.
LoadSampleEnvironment now correctly takes into account scale for translation. Rotation is now applied before translation to reduce confusion.
New IDF have been added for VULCAN.

HRPD Absorption corrections now correctly takes into account the thickness of the slab.
Pearl no longer produces an output of NaN when long-mode is changed after focusing.
Fixed a bug where enabling absorption corrections on GEM raised an error.
LoadILLDiffraction if fixed to load also single point scans.
AlignAndFocusPowderFromFiles no longer errors out if the first chunk has no events

Changed focus to save out .his files in the format <run-number><instrument> as opposed to <run-number>_<instrument> to allow for better compatibility with opengenie.
Added sample environment file for POWGEN that includes many of the standard sample containers

Prevented crash caused by canceling algorithms called by GUI.
Prevented GUI breaking bug caused by entering files from the wrong instrument to calibration.
Prevented issue with reading CSV files on python 3
GUI now correctly loads the file browsed to instead of looking for a run number in every folder along the path to that file.
MDNorm will not crash if the detector is masked in the flux workspace, but not in the input workspace.

New algorithm PredictSatellitePeaks to predict satellite peaks using modulation vectors and maximum order of satellite from PeaksWorkspace or range of wavelength and DSpacing.
New algorithm IndexPeaksWithSatellites to index peaks with satellites and set modulation vectors and maximum order of satellite from input values.

LoadIsawPeaks will load satellite peaks using the order of each satellite by the hkl of the nuclear peak and the mnp of the satellite peak.
SaveIsawPeaks will save satellite peaks using the order of each satellite by the hkl of the nuclear peak and the mnp of the satellite peak.
FindUBUsingIndexedPeaks finds UB matrix using the indexed peaks, modulation vectors and maximum order of satellite from PeaksWorkspace.
IndexPeaks now will also index satellite peaks using modulation vectors and maximum order of satellite from PeaksWorkspace.
IntegrateEllipsoids will integrate peaks using the indexed peaks, modulation vectors and maximum order of satellite from PeaksWorkspace
DeltaPDF3D has a new method for peak removal, KAREN (K-space Algorithmic REconstructioN)
New TOPAZ instrument geometry for 2019B run cycle
Maximum order of modulated vectors is now available to python: ws.sample().getOrientedLattice().getMaxOrder()

MDNorm now checks for consistent binning between the given parameters and the input accumulation workspaces if the latter are given.
StatisticsOfPeaksWorkspace now only calculates statistics for integer HKL (not satellite peaks) instead of combining. Statistics for satellite peaks will be added later.