statistics-surface not compatible with Matlab R2019b

[alexandreroutier]

Feedback from a Clinica user:

When running statistics-surface with Matlab R2019b, the following error is raised:

Standard error:
MATLAB code threw an exception:
Error: File: /Users/alexandre.routier/Projects/Git/clinica_dep/clinica/lib/clinicasurfstat/clinicasurfstat.m Line: 158 Column: 23
Indexing with parentheses '()' must appear as the last operation of a valid indexing expression.
File:/private/var/folders/m_/j76n37kn4vs6zsj8fq0qcgy0000dn9/T/tmpga40_rup/statistics-surface/surfstat/pyscript.m
Name:pyscript
Line:6
Return code: 0

The line involved in pyscript.m is:

            factor1 = char(term(tsvdata{indexunique})){1};

It turns out that using older version of Matlab (when I tested with R2018b), the pipeline runs without issue.

[alexandreroutier]

Solution can be found here and is implemented in PR #98.