Note: before using this routine, please read the Users' Note for your implementation to check the interpretation of bold italicised terms and other implementation-dependent details.
The routine may be called by its
BLAS
name blas_dsum.
3 Description
F16ELF (BLAS_DSUM) returns the sum
x1+x2+⋯+xn
of the elements of an n-element real vector x, via the function name.
If
N≤0 on entry, F16ELF (BLAS_DSUM) returns the value 0.
4 References
Basic Linear Algebra Subprograms Technical (BLAST) Forum (2001) Basic Linear Algebra Subprograms Technical (BLAST) Forum Standard University of Tennessee, Knoxville, Tennessee http://www.netlib.org/blas/blast-forum/blas-report.pdf
5 Parameters
1: N – INTEGERInput
On entry: n, the number of elements in x.
2: X(1+N-1×INCX) – double precision arrayInput
On entry: the vector x. Element xi is stored in
Xi-1×INCX+1,
for i=1,2,…,n.
3: INCX – INTEGERInput
On entry: the increment in the subscripts of X between successive elements of x.
Constraint:
INCX≠0.
6 Error Indicators and Warnings
If INCX=0, an error message is printed and program execution is terminated.