remainder
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header <math.h>
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|   float       remainderf( float x, float y );  | 
(since C99) | |
|   double      remainder( double x, double y );  | 
(since C99) | |
|   long double remainderl( long double x, long double y );  | 
(since C99) | |
Computes the remainder of the floating point division operation x/y.  In difference to fmod, the return type will be negative if fmod(x, y)>y/2.
[edit] Parameters
| x, y | - | floating point values | 
[edit] Return value
Remainder of dividing arguments
[edit] See also
|    remainder of the floating point division operation  (function)  | |
|    (C99)  | 
   the quotient and remainder of integer division  (function)  | 
|   C++ documentation for remainder 
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