How to make a modulo operation in objective-c / cocoa touch?

问题

I have two CGFloat values, and want to calculate the modulo result. Or in other words: I want to know what\'s left if valueA is placed as much as possible into valueB.

So I just tried:

CGFloat moduloResult = valueB % valueA;

the compiler complains about the % and tells me: \"invalid operands to binary %\". Any idea?

回答1:

% is for int or long, not float or double.

You can use fmod() or fmodf() from <math.h> instead.

Better is <tgmath.h> as suggested by the inventor of CGFloat.

回答2:

If I remember correctly modulo requires 2 ints as its input so you'd need something like:

CGFloat moduloResult = (float)((int)valueB % (int)valueA);

Assuming that valueB and valueA are both floats

来源：https://stackoverflow.com/questions/1271102/how-to-make-a-modulo-operation-in-objective-c-cocoa-touch