[Bostonian]

I think Fortran is the closest compiled language to Matlab (both have multidimensional arrays with 1-based indexing), so modern Fortran could be considered for the conversion. Some sites are https://fortran-lang.org/ and for Matlab-Fortran interoperability and partial translation, http://fortranwiki.org/fortran/show/Matlab . A good forum is https://fortran-lang.discourse.group/ .