Symbolic computations
Description of issue:
If coefficients etc can be strings it should be possible to generate symbolic expressions for e.g. transfer functions. For example, SymPy, https://www.sympy.org/en/index.html, can be used for the symbolic expression generation (it should be possible to use evaluate, but on symbolic arguments. Also, using dot2tex, https://dot2tex.readthedocs.io/en/latest/, it can be possible to generate graphs with LaTeX rendering of symbols etc.
Comment:
One may also consider if one should support LaTeX naming of operations for plots, either automatically as SymPy does (A1 becomes A_1, so the 1 is subscripted) or at least turn on LaTeX rendering if the name includes a {.