Sometimes you can! Checkout: https://randomascii.wordpress.com/2014/01/27/theres-only-four-billion-floatsso-test-them-all/ https://randomascii.wordpress.com/20

Sometimes you can! Checkout: https://randomascii.wordpress.com/2014/01/27/theres-only-four-billion-floatsso-test-them-all/ https://randomascii.wordpress.com/2014/01/27/theres-only-fou... From it: Floating-point math is hard, but testing these functions is trivial, and fast. Just do it. The functions ceil, floor, and round are particularly easy to test because there are presumed-good CRT (C RunTime) functions that you can check them against. And, you can test every float bit-pattern (all four billion!) in about ninety seconds. It’s actually very easy. Just iterate through all four-billion (technically 2^32) bit patterns, call your test function, call your reference function, and make sure the results match. Properly comparing NaN and zero results takes a bit of care but it’s still not too bad.