pow, powf, powl
Calculates x raised to the power of y.
double pow(
double x,
double y
);
double pow(
double x,
int y
); // C++ only
float pow(
float x,
float y
); // C++ only
float pow(
float x,
int y
); // C++ only
long double pow(
long double x,
long double y
); // C++ only
long double pow(
long double x,
int y
); // C++ only
float powf(
float x,
float y
);
long double powl(
long double x,
long double y
);
Parameters
x
Base.y
Exponent.
Return Value
Returns the value of xy. No error message is printed on overflow or underflow.
Values of x and y |
Return value of pow |
|---|---|
x < > 0 and y = 0.0 |
1 |
x = 0.0 and y = 0.0 |
1 |
x = 0.0 and y < 0 |
INF |
Remarks
pow does not recognize integral floating-point values greater than 264 (for example, 1.0E100).
pow has an implementation that uses Streaming SIMD Extensions 2 (SSE2). For information and restrictions about using the SSE2 implementation, see _set_SSE2_enable.
Because C++ allows overloading, you can call any of the various overloads of pow. In a C program, pow always takes two double values and returns a double value.
The pow(int, int) overload is no longer available. If you use this overload, the compiler may emit C2668. To avoid this problem, cast the first parameter to double, float, or long double.
Requirements
Routine |
Required header |
|---|---|
pow, powf, powl |
<math.h> |
For additional compatibility information, see Compatibility.
Libraries
All versions of the C run-time libraries.
Example
// crt_pow.c
#include <math.h>
#include <stdio.h>
int main( void )
{
double x = 2.0, y = 3.0, z;
z = pow( x, y );
printf( "%.1f to the power of %.1f is %.1f\n", x, y, z );
}
Output
2.0 to the power of 3.0 is 8.0