An irrational number can only be represented by a computer in an abstract form (obviously) so if all youre doing is multiplication, division, addition and subtraction and nothing to do with logarithms, roots, or an operation with pi or e, theres no reason to consider irrational numbers. I understand you want a name that represents any number from 0 to 1, which technically is an infinite set including irrational and infinitesimals, but it appears this name doesent exist. I would call it something like a positive subunitary proportion.