using % on a double in c++

Question

im trying to use the % operator on a double in c++, i have done the same in java and it works fine.

is there something im missing here or is this not allowed, sorry im new to c++ so might be making a really stupid error here

    double i =  full_price_in_pence / 100.0;
    double j = full_price_in_pence % 100;
    int final_pounds = (int) i;
    int final_pence = (int) j;

and these are both double values

full_price_in_pence
full_price_in_pounds

You _don't want_ to use a double to represent money. At least, not in a real application. — Chad, Mar 22 '13 at 15:45
See this post: http://stackoverflow.com/questions/9138790/cant-use-modulus-on-doubles — gongzhitaao, Mar 22 '13 at 15:47

score 9 · Accepted Answer · answered Mar 22 '13 at 15:46

9

You should use the std::fmod() function from the <cmath> Standard header:

#include <cmath>

// ...

double j = fmod(full_price_in_pence, 100);

answered Mar 22 '13 at 15:46

Andy Prowl

score 3 · Answer 2 · answered Mar 22 '13 at 15:45

3

% is for integers only, you're looking for fmod.

answered Mar 22 '13 at 15:45

Femaref

score 2 · Answer 3 · edited May 23 '17 at 11:50

2

You cannot use % operator for a double variable. Only int variables are allowed to do that.

You can check some good answers from another question like this; you can find them here.

edited May 23 '17 at 11:50

Community

answered Mar 22 '13 at 15:46

George Netu

score 1 · Answer 4 · answered Mar 22 '13 at 15:46

1

No, it's not allowed. Operands of the % operator must be of integral types. Use std::fmod() instead.

answered Mar 22 '13 at 15:46

4 Answers4