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| pow |
| Portability: | ISO/ANSI C conforming, UNIX compatible |
| SYNOPSIS | |
| DESCRIPTION | |
| RETURN VALUE | |
| DIAGNOSTICS | |
| EXAMPLE | |
| RELATED FUNCTIONS | |
| SEE ALSO |
| SYNOPSIS |
#include <math.h> double pow(double x, double y);
| DESCRIPTION |
pow
computes the value of
x
raised to the power
y
, as expressed by this relation:
r = xy
| RETURN VALUE |
pow
returns the value of its argument
x
raised
to the power
y
. The result is a double-precision,
floating-point number.
| DIAGNOSTICS |
If
x
y is too large to be represented, the run-time library writes
an error message to the standard error file (
stderr
) and returns ±
HUGE_VAL
. If
x
y
is too small to be represented, the run-time library writes an error message
to the standard error file (
stderr
) and
returns 0.0.
For a negative value of
x
and a noninteger
y
, the function
returns 0.0, and the run-time library writes an error message to
stderr
. For
x == 0.0
and negative
y
, the function returns
HUGE_VAL
, and the run-time library writes an error message to
stderr
.
If an
error occurs in
pow
, the
_matherr
routine is called.
You can supply your own version of
_matherr
to suppress the diagnostic message or modify the value returned.
| EXAMPLE |
This example finds the cube root of 17,
using
pow
:
#include <math.h>
#include <stdio.h>
main()
{
double x, y, f;
x = 17.0;
y = 1.0/3.0;
f = pow(x, y);
printf("(pow(%f,%f)) = %f\n", x, y, f);
}
| RELATED FUNCTIONS |
| SEE ALSO |
|
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Copyright © 2001 by SAS Institute Inc., Cary, NC, USA. All rights reserved.