I am a PhD student in applied math, working in the field of numerical analysis for partial differential equations. The library I'm (humbly) trying to help to develop is written in c++, using mpi for the parallelism issues. My background other than c++ is pretty low, so I can't say that I KNOW any programming language other than that (although I have coded something back in the days in Python and SQL, but it was too little and too 'scholastic' to claim I know it...also, I forgot most of it).

In math I have a somewhat deep knowledge in analysis, matrix analysis, numerical analysis, partial differential equations, Navier-Stokes equations and optimization. But I can't say I'm an expert in any of the above fields...although, I try my best. =)