Since there are so many CS related SEs I am not sure where I should ask this particular question. I have Fortran 77 code that uses complicated expressions to calculate a number and I have encountered a underflow error in that code. I have refactored the code into fortran 90 into more simpler expressions and come up with a way to handle the underflow error. I am not able to reproduce the numbers produced by a colleague regarding convergence of that algorithm. Would this question be on topic here - my handling of the underflow error and refactoring of the code ?