trunc
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header <math.h>
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|   float       truncf( float arg );  | 
(since C99) | |
|   double      trunc( double arg );  | 
(since C99) | |
|   long double truncl( long double arg );  | 
(since C99) | |
Computes nearest integer not greater in magnitude than arg. 
Contents | 
[edit] Parameters
| arg | - | floating point value | 
[edit] Return value
Nearest integer not greater in magnitude than arg. 
[edit] Notes
The integer value can be always represented by the given floating point type.
[edit] See also
|    nearest integer not greater than the given value   (function)  | |
|    nearest integer not less than the given value   (function)  | |
|    (C99) (C99) (C99)  | 
   nearest integer, rounding away from zero in halfway cases   (function)  | 
|   C++ documentation for trunc 
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