I would like to know your opinion about which is the best code to work with mathematical operations/structures.
I am doing my thesis on symmetric polynomials and I would like to include a computational part. Now I am trying to compute Schur functions, but C is not the best code to do so. What do you think?
When I talk about programming, I mean to do like a console application where you can ask someone to put an input and things like that.
Do you have access to MAGMA? There seem to be a number of functions related to what you have in mind here at https://magma.maths.usyd.edu.au/magma/handbook/text/1762.
Of course, MAGMA comes at a cost, though your institution may have paid the license. SAGE math is free, has a similar amount of functionality, and seems also to have functions of this kind built in: http://doc.sagemath.org/html/en/reference/combinat/sage/combinat/sf/schur.html
The best way to run MAGMA is via a Jupyter notebook, while SAGE works best via https://cocalc.com/
Good luck!