pow(), powf(), powl()

Raise a number to a given power

Synopsis:

#include <math.h>

double pow( double x, 
            double y );

float powf( float x, 
            float y );

long double powl( long double x,
                  long double y );

Since:

BlackBerry 10.0.0

Arguments:

x
The number you want to raise.
y
The power you want to raise the number to.

Library:

libm

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

Description:

The pow(), powf(), and powl() functions compute x raised to the power of y.

A domain error occurs if x = 0, and y0, or if x is negative, and y isn't an integer. A range error may also occur.

Returns:

The value of x y . For finite values of x less than 0 and finite non-integer values of y, these functions return NaN. The return value for a correct value that would cause underflow is 0.0.

If an error occurs, these functions return 0, but this is also a valid mathematical result. If you want to check for errors, set errno to 0, call the function, and then check errno again. These functions don't change errno if no errors occurred.

Examples:

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

int main( void )
{
    printf( "%f\n", pow( 1.5, 2.5 ) );
    
    return EXIT_SUCCESS;
}

produces the output:

2.755676

Classification:

ANSI, POSIX 1003.1

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

Last modified: 2014-06-24



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