Contents


NAME

     zdotci - Compute the complex conjugated indexed dot product.

SYNOPSIS

      DOUBLE COMPLEX FUNCTION ZDOTCI(NZ, X, INDX, Y)

      DOUBLE COMPLEX X(*), Y(*)
      INTEGER NZ
      INTEGER INDX(*)

      DOUBLE COMPLEX FUNCTION ZDOTCI_64(NZ, X, INDX, Y)

      DOUBLE COMPLEX X(*), Y(*)
      INTEGER*8 NZ
      INTEGER*8 INDX(*)

     F95 INTERFACE
      DOUBLE COMPLEX FUNCTION DOTCI([NZ], X, INDX, Y)

      COMPLEX(8), DIMENSION(:) :: X, Y
      INTEGER :: NZ
      INTEGER, DIMENSION(:) :: INDX

      DOUBLE COMPLEX FUNCTION DOTCI_64([NZ], X, INDX, Y)

      COMPLEX(8), DIMENSION(:) :: X, Y
      INTEGER(8) :: NZ
      INTEGER(8), DIMENSION(:) :: INDX

PURPOSE

     ZDOTCI Compute the complex conjugated indexed dot product of
     a complex sparse vector x stored in compressed form with a
     complex vector y in full storage form.

      dot = 0
      do i = 1, n
        dot = dot + conjg(x(i)) * y(indx(i))
      enddo

ARGUMENTS

     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.