Visible to Intel only — GUID: GUID-118B1085-9190-476D-9942-30860D50F37C
Visible to Intel only — GUID: GUID-118B1085-9190-476D-9942-30860D50F37C
?doti
Computes the dot product of a compressed sparse real vector by a full-storage real vector.
Syntax
res = sdoti(nz, x, indx, y )
res = ddoti(nz, x, indx, y )
res = doti(x, indx, y)
Include Files
- mkl.fi, blas.f90
Description
The ?doti routines return the dot product of x and y defined as
res = x(1)*y(indx(1)) + x(2)*y(indx(2)) +...+ x(nz)*y(indx(nz))
where the triple (nz, x, indx) defines a sparse real vector stored in compressed form, and y is a real vector in full storage form. The functions reference only the elements of y whose indices are listed in the array indx. The values in indx must be distinct.
Input Parameters
- nz
-
INTEGER. The number of elements in x and indx .
- x
-
REAL for sdoti
DOUBLE PRECISION for ddoti
Array, size at least nz.
- indx
-
INTEGER. Specifies the indices for the elements of x.
Array, size at least nz.
- y
-
REAL for sdoti
DOUBLE PRECISION for ddoti
Array, size at least max(indx(i)).
Output Parameters
- res
-
REAL for sdoti
DOUBLE PRECISION for ddoti
Contains the dot product of x and y, if nz is positive. Otherwise, res contains 0.
BLAS 95 Interface Notes
Routines in Fortran 95 interface have fewer arguments in the calling sequence than their FORTRAN 77 counterparts. For general conventions applied to skip redundant or reconstructible arguments, see BLAS 95 Interface Conventions.
Specific details for the routine doti interface are the following:
- x
-
Holds the vector with the number of elements nz.
- indx
-
Holds the vector with the number of elements nz.
- y
-
Holds the vector with the number of elements nz.