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GrainSpotter

GrainSpotter is a software which looks for grains in a 2D diffraction image.

To run it, you need a file with the ending .ini. When you perform a simulation with PolyXSim, it should automatically create such a file. It usually looks like this:

  spacegroup 136                       ! spacegroup [space group nr]
  !dsrange 0 4.2                       ! dsrange [min max], d-spacing range, multiple ranges can be specified
  tthrange 0 25                        ! tthrange [min max], multiple ranges can be specified
  etarange 0 360                       ! etarange [min max], multiple ranges can be specified
  domega 0.5                           ! domega [stepsize] in omega, degrees 
  omegarange -28 28                    ! omegarange [min max] degrees, multiple ranges can be specified
  filespecs g_vectors.gve grains.log   ! filespecs [gvecsfile grainsfile] 
  cuts 5 0.6 0.8                       ! cuts [min_measuments min_completeness min_uniqueness]
  eulerstep 6                          ! eulerstep [stepsize] : angle step size in Euler space
  uncertainties 0.1 0.2 .5    	       ! uncertainties [sigma_tth sigma_eta sigma_omega] in degrees
  nsigmas 2                   	       ! nsigmas [Nsig] : maximal deviation in sigmas
  !minfracg 0.2                        ! stop search when minfracg (0..1) of the gvectors have been assigned to grains 
  !Nhkls_in_indexing 15		       ! Nhkls_in_indexing [Nfamilies] : use first Nfamilies in indexing
  random 10000                         ! use randomly chosen orientation seeds #trials
  !positionfit                         ! fit the position of the grain

Explanations of the .ini file:

spacegroup	enter the space group number
dsrange	…

cut_first number	grain is chosen if there are at least this amount of peaks per grain
cut_second number	grain is chosen if there are at least this fraction of the expected peaks present
cut_third number	put in any number