Base converter with fractions?

[Jan_D]

When we consider the program as a black box your code is certainly more professional than my simplified one.
But when we are interested in understanding the program, and possibly modify it, I prefer the other.
It should not be a problem that we reserve one CAS variable, say tmp or ex1, ex2, for use of programs, there are enough variables left.

Built - in apps like the Function app or Advanced Graphing also change the content of X and Y, which could be considered more serious.
The advantage of this is however that by doing this they can very effectively collaborate with e.g. the Solve app.