kml_sparse_?dotui_sub
复数域的非共轭点积（欧几里得空间）；x · y = xˆT * y，即对应元素相乘然后累加。
res = x[0] * y[indx[0]] + x[1] * y(indx[1]) + ... + x[nz - 1] * y[indx[nz - 1]]
接口定义
C interface:
kml_sparse_status_t kml_sparse_cdotui_sub(const KML_INT nz, const KML_Complex8 *x, const KML_INT *indx, const KML_Complex8 *y, KML_Complex8 *dotui);
kml_sparse_status_t kml_sparse_zdotui_sub(const KML_INT nz, const KML_Complex16 *x, const KML_INT *indx,const KML_Complex16 *y, KML_Complex16 *dotui);
Fortran interface:
RES = KML_SPARSE_CDOTUI_SUB(NZ, X, INDX, Y, DOTUI);
RES = KML_SPARSE_ZDOTUI_SUB(NZ, X, INDX, Y, DOTUI);
参数
参数名 |
类型 |
描述 |
输入/输出 |
|---|---|---|---|
nz |
整型数 |
x及indx数组中元素的个数。 |
输入 |
x |
|
存储非零元素的数组x，大于或等于nz。 |
输入 |
indx |
整型数组 |
indx[i]表示x数组中第i个元素在稠密向量中的序列号，数组大小大于或等于nz。 |
输入 |
y |
|
数组y，大于或等于max(indx[i])。 |
输入 |
dotui |
|
x与y的点积。 |
输入/输出 |
返回值
函数执行状态，枚举类型kml_sparse_status_t。
依赖
C: "kspblas.h"
Fortran: "kspblas.f03"
示例
C interface:
KML_INT nz = 2;
KML_Complex8 dotui = {0,0};
KML_INT indx[2] = {1, 2};
KML_Complex8 x[2] = {{1, 2}, {3, 4}};
KML_Complex8 y[4] = {{-1, 1}, {5, 3}, {-2, -3}, {4, 1}};
kml_sparse_status_t status = kml_sparse_cdotui_sub(nz, x, indx, y, &dotui);
/*
* Output dotui:
* {5.000000, -4.000000}
*/
Fortran interface:
INTEGER(C_INT) :: NZ = 2
INTEGER(C_INT) :: STATUS
INTEGER(C_INT) :: I
TYPE(KML_COMPLEX8), TARGET :: DOTUI = KML_COMPLEX8(0, 0)
INTEGER(C_INT) :: INDX(2)
TYPE(KML_COMPLEX8) :: CX(2), Y(4)
REAL(C_FLOAT) :: X(4), Y(8)
TYPE(C_PTR) :: PDOTCUI
PDOTUI = C_LOC(DOTUI)
DATA INDX/1, 2/
DATA X/1, 2, 3, 4/
DATA Y /-1, 1, 5, 3, -2, -3, 4, 1/
I = 1
DO WHILE(I <= 2)
CX(I)%REAL = X(2 * I - 1)
CX(I)%IMAG = X(2 * I)
END DO
I = 1
DO WHILE(I <= 4)
CY(I)%REAL = Y(2 * I - 1)
CY(I)%IMAG = Y(2 * I)
END DO
STATUS = KML_SPARSE_CDOTUI_SUB(NZ, CX, INDX, CY, PDOTUI)
!
! OUTPUT DOTCI:
! {5.000000, -4.000000}
!