Contents
sdoti - Compute the indexed dot product.
REAL FUNCTION SDOTI(NZ, X, INDX, Y)
REAL X(*), Y(*)
INTEGER NZ
INTEGER INDX(*)
REAL FUNCTION SDOTI_64(NZ, X, INDX, Y)
REAL X(*), Y(*)
INTEGER*8 NZ
INTEGER*8 INDX(*)
F95 INTERFACE
REAL FUNCTION DOTI([NZ], X, INDX, Y)
REAL, DIMENSION(:) :: X, Y
INTEGER :: NZ
INTEGER, DIMENSION(:) :: INDX
REAL FUNCTION DOTI_64([NZ], X, INDX, Y)
REAL, DIMENSION(:) :: X, Y
INTEGER(8) :: NZ
INTEGER(8), DIMENSION(:) :: INDX
SDOTI Compute the indexed dot product of a real sparse
vector x stored in compressed form with a real vector y in
full storage form.
dot = 0
do i = 1, n
dot = dot + x(i) * y(indx(i))
enddo
NZ (input)
Number of elements in the compressed form.
Unchanged on exit.
X (input)
Vector in compressed form. Unchanged on exit.
INDX (input)
Vector containing the indices of the compressed
form. It is assumed that the elements in INDX are
distinct and greater than zero. Unchanged on exit.
Y (input)
Vector in full storage form. Only the elements
corresponding to the indices in INDX will be
accessed.