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 );
Arguments:
- x
- The number you want to raise.
- y
- The power you want to raise the number to.
Description:
The pow(), powf(), and powl() functions compute x raised to the power of y.
A domain error occurs if x = 0, and y ≤ 0, or if x is negative, and y isn't an integer. A range error may also occur.
Returns:
The value of xy. 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:
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | No |
| Thread | Yes |