Diffraction Changes

Documentation

  • The documentation for all calibration approaches, including Powder diffraction, single crystal and engineering calibrations has been pulled together, and expanded here.

Powder Diffraction

Powder Diffraction Scripts

  • Pearl powder diffraction has been integrated and can be found scripts/PearlPowderISIS. The routines/script has been differentiated from the long list of directories of calibration and raw files. The calibration directories can be found in a file by the name of pearl_calib_factory.py, whereas the raw directories can be found in a file by the name of pearl_cycle_factory.py.
  • PowderISIS script has been renamed to CryPowderISIS and can be found within the following folder scripts/CryPowderISIS
  • Pearl Powder Diffraction Script documentation has been implemented and PowderISIS script documentation has been renamed to Crystallography Powder Diffraction Script

Single Crystal Improvements

  • SCDCalibratePanels has parameter errors reduced, an option for simplex minimization, and 3 new workspaces which can plot calculated vs theoretical columns, rows, and TOF for each bank. Calibration is now as good as ISAW’s for Mandi data.
  • 5 detectors added to the MANDI instrument geometry
  • LoadCIF can now also load structures where only anisotropic displacement parameters are given, which are converted to equivalent isotropic parameters.
  • SaveHKL has option to write the same output as anvred3.py including direction cosines.
  • LoadHKL reads hkl output that includes direction cosines.
  • SaveIsawPeaks has DetCal information sorted by detector numbers
  • StatisticsOfPeaksWorkspace has resolution shells in units of d-Spacing.
  • SpaceGroup now has a method to check whether a specified unit cell is compatible with the symmetry operations of the group.

Engineering Diffraction

  • The new algorithm GSASIIRefineFitPeaks can be used to call the GSAS-II software repeatedly to refine lattice parameters (whole pattern refinement) and/or fit peaks.
  • New algorithm added: EnggFitDIFCFromPeaks, which forks from the old EnggFitPeaks. EnggFitPeaks modified to fit peaks but not calibration parameters.
  • An option to set the initial rebin width has been added to EnggCalibrateFull
  • EnggFocus now has an option to mask out several ranges in ToF (instrument pulses), with default values set for ENGIN-X, and an option to normalize by proton charge (enabled by default).
  • Phase information files for ENGIN-X are now distributed together with the ENGIN-X scripts.
  • New algorithm SaveNexusPD which creates a nexus file for use in GUDRUN and will hopefully be supported by Rietveld packages in the future.

Graphical user interface

  • Vanadium Curves and Ceria Peaks graphs are plotted once basic and cropped calibration process has been carried out
  • Customise Bank Name text-field will set the workspace and .his file name according to this Bank Name provided by the user for Cropped Calibration
  • The Fitting tab provides a graphical interface which fits an expected diffraction pattern and visualises them. The pastern is specified by providing a list of dSpacing values where Bragg peaks are expected. The algorithm EnggFitPeaks used in the background fit peaks in those areas using a peak fitting function.
  • Fitting tab will automatically select and import all the focused bank files found within working directory and user can also select file now by providing a run-number.
  • Improvements to the Preview section for Fitting tab, the zoom-in or zoom-out feature on to the data plot is enabled. As well as option to select peak, add peak or save peaks from the data plot is now supported.
  • Preview under Fitting tab, you can now view the plot in dSpacing instead ToF, which enables you to rerun the fitting process after selecting peaks from the interface.
  • The output calibration files will be written with the extension ”.prm” by default. Together with an “all-banks” calibration (GSAS instrument parameters) file, an individual file for every focused bank will be written.
  • Improvements to Fitting tab, Single peak fitting for consecutive run number’s focused files has now been enabled. The tab will automatically load the consecutive run numbers to the list widget from the range provided by the user, bank combo-box will update upon selection of run number.
  • Further improvements to Fitting tab, if for some reason the fitting fails, the focused workspace should still be plotted. This will enable user to select valid peaks and run Fit accordingly. User also now have an option to plot single peak fitting in separate workspace by using Plot To Separate Window button. Peak list can now also be cleared using the Clear button.

Imaging

  • The new algorithm ImggAggregateWavelengths aggregates stacks of images from wavelength dependent data.
  • The algorithm ImggTomographicReconstruction has been introduced. This is a first experimental version that implements the Filtered Back-Projection (FBP) reconstruction method using the FBP implementation of the TomoPy package.
  • Images loaded as Mantid workspaces can now be saved into FITS files using the algorithm SaveFITS.

Improvements in the tomographic reconstruction graphical user interface

  • New capabilities added when visualizing stacks of images:
    • Handle the rotation of all the images in the stack
    • “Play” the stack or sequence of images as a movie
    • Visualize sample, flat, and dark images separately
    • Multiple color map alternatives and control of the color bar
  • Previously existing parameters to set up local and remote paths have been moved into a new section of the interface. New options have been introduced for better flexibility. These are updated for the current infrastructure and are remembered between sessions.
  • Normalization by flat and dark images can be disabled explicitly and separately, which is now supported in the underlying reconstruction scripts.
  • The energy bands tab can now produce multiple output bands in one pass, and supports different aggregation methods via the new algorithm ImggAggregateWavelengths.

Full list of diffraction and imaging changes on GitHub.