fmri_sub2mni
============

.. currentmodule:: fmri_toolbox

Description
-----------
FMRI_SUB2MNI  Converts voxel subscripts to MNI coordinates (mm).
Converts one or more voxel indices (in the 91x109x91 MATLAB 1-based
subscript space) to MNI152 coordinates in millimetres, using the standard
2mm isotropic MNI152 template origin.

Usage
-----
.. code-block:: matlab

    mni = fmri_sub2mni(sub)

Inputs
------
- **SUB**: Voxel subscripts, (N x 3) matrix: [x1 y1 z1; x2 y2 z2; ...]. Subscripts are 1-based (MATLAB convention), x in [1 91], y in [1 109], z in [1 91].

Outputs
-------
- **MNI**: MNI coordinates in mm, (N x 3) matrix: [x1 y1 z1; ...]. MNI [0 0 0] corresponds to subscript [46 64 37].

Examples
--------
.. code-block:: matlab

    mni = fmri_sub2mni([46 64 37]);       % returns [0 0 0]
    mni = fmri_sub2mni([46 64 37; 1 1 1])

Notes
-----
- Origin is [46 64 37] (1-indexed), corresponding to the MNI152 2mm
- anterior commissure. Voxel size is 2mm isotropic.
- Inverse function: fmri_mni2sub.

See Also
--------
- fmri_mni2sub
- fmri_mni2tal
- fmri_ind2sub
- fmri_regionnumber