v?cos
Interface Definition
C interface:
void vscos(const int len, const float* src, float* dst);
void vdcos(const int len, const double* src, double* dst);
void vccos(const int len, const float complex *src, float complex *dst);
void vzcos(const int len, const double complex *src, double complex *dst);
Fortran interface:
CALL VSCOS(LEN, SRC, DST);
CALL VDCOS(LEN, SRC, 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 |
src |
|
Input vector src with length len. If the pointer is null, the system prompts a null pointer error. |
Input |
dst |
|
Output vector dst with length len. If the pointer is null, the system prompts a null pointer error. |
Output |
Return Value
- The cosine y of radian angle x is returned for each operation value, that is, y = cos(x). y ∈ [-1, +1]
- For special values, see the following table.
Input Value (src)
Output Value (dst)
±inf
nan
±0
+1
nan
nan
Dependency
C: "kvml.h"
Examples
C interface:
int i, len = 4;
float src[len] = {0.0f, 2.0f, inf, nan};
float* dst = (float*)malloc(sizeof(float) * len);
if (dst == NULL) {
printf("Malloc Failed!\n");
return 0;
}
vscos(len, src, dst);
/**
* Output dst:
* 1.0 -0.416146814823151 nan nan
*
*/
Fortran interface:
INTEGER :: LEN = 4
REAL(4) SRC(4)
REAL(4) DST(4)
DATA SRC /1, 2, 3, 4/
CALL VSCOS(LEN, SRC, DST)
!
! OUTPUT DST:
! 0.540302277, -0.416146815, -0.989992499, -0.653643608
!