floor(), floorf(), floorl()

Round down a value to the next integer

Synopsis:

#include <math.h>

double floor( double x );

float floorf( float x );

long double floorl(long double x);

Arguments:

x
The value you want to round.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

The floor(), floorf(), and floorl() functions compute the largest integer less than or equal to x (rounding towards the “floor”). If x is ±0 or ±Inf, these functions return x. If x is NaN, these functions return NaN.

Returns:

The largest integer less than or equal to x.

Examples:

#include <stdio.h>
#include <math.h>
#include <stdlib.h>

int main( void )
{
    printf( "%f\n", floor( -3.14 ) );
    printf( "%f\n", floor( -3. ) );
    printf( "%f\n", floor( 0. ) );
    printf( "%f\n", floor( 3.14 ) );
    printf( "%f\n", floor( 3. ) );

    return EXIT_SUCCESS;
}

produces the output:

-4.000000
-3.000000
0.000000
3.000000
3.000000

Classification:

ANSI, POSIX 1003.1

Safety:  
Cancellation point No
Interrupt handler No
Signal handler No
Thread Yes