Intel® Math Kernel Library 2018 Developer Reference - C
Computes the sum of magnitudes of the vector elements.
float cblas_sasum (const MKL_INT n, const float *x, const MKL_INT incx);
float cblas_scasum (const MKL_INT n, const void *x, const MKL_INT incx);
double cblas_dasum (const MKL_INT n, const double *x, const MKL_INT incx);
double cblas_dzasum (const MKL_INT n, const void *x, const MKL_INT incx);
The ?asum routine computes the sum of the magnitudes of elements of a real vector, or the sum of magnitudes of the real and imaginary parts of elements of a complex vector:
res = |Re x1| + |Im x1| + |Re x2| + |Im x2|+ ... + |Re xn| + |Im xn|,
where x is a vector with n elements.
Specifies the number of elements in vector x.
Array, size at least (1 + (n-1)*abs(incx)).
Specifies the increment for indexing vector x.
Contains the sum of magnitudes of real and imaginary parts of all elements of the vector.