v?powr

Compute a variable raised to a power. The variable, power, and result are vectors, and the variable ≥ 0.

Interface Definition

C interface:

void vspowr(const int len, const float* src1, const float* src2, float* dst);

void vdpowr(const int len, const double* src1, const double* src2, double* dst);

Parameters

Parameter	Type	Description	Input/Output
len	Integer	Number of elements in the input vector. If len ≤ 0, the system displays a message indicating that the value of len is invalid.	Input
src1	Single-precision floating-point type for vspowr Double-precision floating-point type for vdpowr	Input vector src1 with length len. If the pointer is null, the system prompts a null pointer error.	Input
src2	Single-precision floating-point type for vspowr Double-precision floating-point type for vdpowr	Input vector src2 with length len. If the pointer is null, the system prompts a null pointer error.	Input
dst	Single-precision floating-point type for vspowr Double-precision floating-point type for vdpowr	Output vector dst with length len. If the pointer is null, the system prompts a null pointer error.	Output

Return Value

Return the calculation result of a^b. For details about special values, see the following table.

Input Value 1 (src1)	Input Value 2 (src2)	Output Value (dst)
x < 0	Any value	NaN
0 < x < inf	±0	1
±0	-inf < y < 0	+inf
±0	-inf	+inf
±0	y > 0	+0
1	-inf < y < +inf	1
±0	±0	1
+inf	±0	1
1	+inf	1
x ≥ 0	NaN	NaN
NaN	Any value	NaN
0 < x < 1	-inf	+inf
x > 1	-inf	+0
0 ≤ x < 1	+inf	+0
x > 1	+inf	+inf
+inf	x < 0	+0
+inf	x > 0	+inf
Any value	NaN	NaN

For other special values, see v?pow.

Dependencies

C: "kvml.h"

Fortran: "kvml.f03"

Examples

C interface:

    int i, len = 4; 
    float src1[len] = {-1.0f, 0.0f, 16.0f, 2.0f}; 
    float src2[len] = {0.0f, 0.0f, 0.5f, 3.0f}; 
    float* dst = (float*)malloc(sizeof(float) * len); 
    if (dst == NULL) { 
        printf("Malloc Failed!\n"); 
        return 0; 
    } 
    vspowr(len, src1, src2, dst); 
    /** 
     *  Output dst: 
     *     nan  1.0  4.0  8.0 
     * 
     */

Parent topic: Function Syntax