Good Afternoon Great_Sushi,
Actually, both are applicable. It really boils down to what process you want.
Matlab has a powerful scripting language, is matrix oriented and has a ton of solvers and operators.
Fortran is a programming language, it probably has libraries to do operations on matrix, solvers and operators. Do these work with each other? Good question.
A third option would be Python with scipy and numpy: it's python with matlab-like extensions. If you add matplotlib, you have a complete solution for the processing AND graphing.