ceil(), ceilf(), ceill()

Arguments:

x

The value you want to round.

Library:

libm

The general-purpose math library.

libm-sve

A library that optimizes the code for ARMv8.2 chips that have Scalable Vector Extension hardware.

Your system requirements will determine how you should work with these libraries:

• If you want only selected processes to run with the SVE version, you can include both libraries in your OS image and use the -l m or -l m-sve option to qcc to link explicitly against the appropriate one.
• If you want all processes to use the SVE version, include libm-sve.so in your OS image and set up a symbolic link from libm.so to libm-sve.so. Use the -l m option to qcc to link against the library.

Description:

The ceil(), ceilf(), and ceill() functions round the value of x up to the next integer (rounding towards the ceiling).

To check for error situations, use feclearexcept() and fetestexcept(). For example:

• Call feclearexcept(FE_ALL_EXCEPT) before calling ceil(), ceilf(), or ceill().
• On return, if fetestexcept(FE_ALL_EXCEPT) is nonzero, then an error has occurred.

Returns:

The smallest integer ≥ x with the same sign as x.

These functions raise FE_INEXACT if the FPU reports that the result can't be exactly represented as a floating-point number.

Examples:

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

int main( void )
{
    printf( "%f %f %f %f %f\n", ceil( -2.1 ), 
      ceil( -2. ), ceil( 0.0 ), ceil( 2. ), 
      ceil( 2.1 ) );

    return EXIT_SUCCESS;
}

produces the output:

-2.000000 -2.000000 0.000000 2.000000 3.000000

Classification:

C11, POSIX 1003.1