Can't Use Modulus on Doubles

Can't use modulus on doubles?

The % operator is for integers. You're looking for the fmod() function.

#include <cmath>

int main()
{
    double x = 6.3;
    double y = 2.0;
    double z = std::fmod(x,y);

}

modulus is not working when using doubles in c++

The modulus operator % is an integral function.

You need to use fmod for floating-point.

How do I use modulus for float/double?

You probably had a typo when you first ran it.

evaluating 0.5 % 0.3 returns '0.2' (A double) as expected.

Mindprod has a good overview of how modulus works in Java.

Why does modulus division (%) only work with integers?

Because the normal mathematical notion of "remainder" is only applicable to integer division. i.e. division that is required to generate integer quotient.

In order to extend the concept of "remainder" to real numbers you have to introduce a new kind of "hybrid" operation that would generate integer quotient for real operands. Core C language does not support such operation, but it is provided as a standard library fmod function, as well as remainder function in C99. (Note that these functions are not the same and have some peculiarities. In particular, they do not follow the rounding rules of integer division.)

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