3dTsort

Usage: 3dTsort [options] dataset
Sorts each voxel and produces a new dataset.

Options:
 -prefix p = use string 'p' for the prefix of the
               output dataset [DEFAULT = 'tsort']
 -inc      = sort into increasing order [default]
 -dec      = sort into decreasing order
 -rank     = output rank instead of sorted values
             ranks range from 1 to Nvals
 -ind      = output sorting index. (0 to Nvals -1)
             See example below.
 -val      = output sorted values (default)
 -random   = randomly shuffle (permute) the time points in each voxel
             * Each voxel is permuted independently!
             * Why is this here? Someone asked for it :)
 -ranFFT   = randomize each time series by scrambling the FFT phase
             * Each voxel is treated separately!
             * Why is this here? cf. Matthew 7:7-8 :)
 -ranDFT   = Almost the same as above, but:
             * In '-ranFFT', the FFT length is taken
               to be the next integer >= data length
               for which the FFT algorithm is efficient.
               This will result in data padding unless
               the data length is exactly 'nice' for FFT.
             * In '-ranDFT', the DFT length is exactly
               the data length. If the data length is
               a large-ish prime number (say 997), this
               operation can be slow.
             * The DFT/FFT algorithm is reasonably fast
               when the data length prime factors contain
               only 2s, 3s, and/or 5s.
             * Using '-ranDFT' can preserve the spectral
               (temporal correlation) structure of the
               original data a little better than '-ranFFT'.
             * The only reason to use '-ranFFT' instead of
               '-ranDFT' is for speed. For example, with
               997 time points, '-ranFFT' was about 13 times
               faster (FFT length=1000) than '-ranDFT'.
 -datum D  = Coerce the output data to be stored as
             the given type D, which may be
             byte, short, or float (default).

Notes:
* Each voxel is sorted (or processed) separately.
* Sub-brick labels are not rearranged!
* This program is useful only in limited cases.
   It was written to sort the -stim_times_IM
   beta weights output by 3dDeconvolve.
* Also see program 1dTsort, for sorting text files of numbers.

Examples:
setenv AFNI_1D_TIME YES
echo '8 6 3 9 2 7' > test.1D
    3dTsort -overwrite test.1D
    1dcat tsort.1D

    3dTsort -overwrite -rank test.1D
    1dcat tsort.1D


    3dTsort -overwrite -ind test.1D
    1dcat tsort.1D

    3dTsort -overwrite -dec test.1D
    1dcat tsort.1D


++ Compile date = Oct 31 2024 {AFNI_24.3.06:linux_ubuntu_24_64}