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POW(3)                   BSD Library Functions Manual                   POW(3)

NAME
     pow -- power function

SYNOPSIS
     #include <math.h>

     double
     pow(double x, double y);

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

     float
     powf(float x, float y);

DESCRIPTION
     The pow() functions compute x raised to the power y.

SPECIAL VALUES
     pow(+-_, y) returns +-infinity and raises the "divide-by-zero" floating-point exception for y an odd
     integer < 0.

     pow(+-_, y) returns +infinity and raises the "divide-by-zero" floating-point exception for y < 0 and
     not an odd integer.

     pow(+-_, y) returns +-0 for y an odd integer > 0.

     pow(+-_, y) returns +0 for y > 0 and not an odd integer.

     pow(-1, +-infinity) returns 1.

     pow(1, y) returns 1 for any y, even a NaN.

     pow(x, +-_) returns 1 for any x, even a NaN.

     pow(x, y) returns a NaN and raises the "invalid" floating-point exception for finite x < 0 and finite
     non-integer y.

     pow(x, -infinity) returns +infinity for |x| < 1.

     pow(x, -infinity) returns +0 for |x| > 1.

     pow(x, +infinity) returns +0 for |x| < 1.

     pow(x, +infinity) returns +infinity for |x| > 1.

     pow(-infinity, y) returns -0 for y an odd integer < 0.

     pow(-infinity, y) returns +0 for y < 0 and not an odd integer.

     pow(-infinity, y) returns -infinity for y an odd integer > 0.

     pow(-infinity, y) returns +infinity for y > 0 and not an odd integer.

     pow(+infinity, y) returns +0 for y < 0.

     pow(+infinity, y) returns +infinity for y > 0.

     A domain error occurs if x is finite and negative and y is finite and not an integer.

     A domain error can occur if x is 0 and y less than or equal to 0.

     Range errors may occur.

VECTOR OPERATIONS
     If you need to apply the pow() functions to SIMD vectors or arrays, using the following functions pro-vided provided
     vided by the Accelerate.framework may give significantly better performance:

     #include <Accelerate/Accelerate.h>

     vFloat vpowf(vFloat x, vFloat y);
     vFloat vpowf(vFloat x, vSInt32 y);
     void vvpowf(float *z, const float *y, const float *x, const int *n);
     void vvpow(double *z, const double *y, const double *x, const int *n);
     void vvpowsf(float *z, const float *y, const float *x, const int *n);
     void vvpows(double *z, const double *y, const double *x, const int *n);

SEE ALSO
     exp (3) математика (3)

STANDARDS
     The pow() function conforms to ISO/IEC 9899:2011.

4th Berkeley Distribution      December 11, 2006     4th Berkeley Distribution