dirflip

Synopsis

Invert the polarity of individual directions so as to optimise a unipolar electrostatic repulsion model

Usage

dirflip [ options ]  in out

  • in: the input files for the directions.

  • out: the output files for the directions.

Description

The orientations themselves are not affected, only their polarity; this is necessary to ensure near-optimal distribution of DW directions for eddy-current correction.

Options

  • -number num number of shuffles to try (default: 100000000)

  • -preserve num preserve the sign of some number of directions at the start of the set

  • -cartesian Output directions in Cartesian coordinates [x y z] instead of spherical angles [az in].

Standard options

  • -info display information messages.

  • -quiet do not display information messages or progress status; alternatively, this can be achieved by setting the MRTRIX_QUIET environment variable to a non-empty string.

  • -debug display debugging messages & debug input data.

  • -force force overwrite of output files (caution: using the same file as input and output might cause unexpected behaviour).

  • -nthreads number use this number of threads in multi-threaded applications (set to 0 to disable multi-threading).

  • -config key value (multiple uses permitted) temporarily set the value of an MRtrix config file entry.

  • -help display this information page and exit.

  • -version display version information and exit.

References

Tournier, J.-D.; Smith, R. E.; Raffelt, D.; Tabbara, R.; Dhollander, T.; Pietsch, M.; Christiaens, D.; Jeurissen, B.; Yeh, C.-H. & Connelly, A. MRtrix3: A fast, flexible and open software framework for medical image processing and visualisation. NeuroImage, 2019, 202, 116137

Author: J-Donald Tournier (jdtournier@gmail.com)

Copyright: Copyright (c) 2008-2026 the MRtrix3 contributors.

This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

Covered Software is provided under this License on an “as is” basis, without warranty of any kind, either expressed, implied, or statutory, including, without limitation, warranties that the Covered Software is free of defects, merchantable, fit for a particular purpose or non-infringing. See the Mozilla Public License v. 2.0 for more details.

For more details, see http://www.mrtrix.org/.