CXML

ssctrs, dsctrs, csctrs, zsctrs 


FORMAT

  {S,D,C,Z}SCTRS ( nz, alpha, x, indx, y )

Arguments

  nz                  integer*4
                      On entry, the number of elements to be scattered from
                      the compressed form.
                      On exit, nz is unchanged.

  alpha               real*4 | real*8 | complex*8 | complex*16
                      On entry, the scalar multiplier for the elements of
                      vector x.
                      On exit, alpha is unchanged.

  x                   real*4 | real*8 | complex*8 | complex*16
                      On entry, an array of the elements of vector x to be
                      scattered from compressed form into full form.
                      On exit, x is unchanged.

  indx                integer*4
                      On entry, an array containing the indices of the values
                      to be scattered from the compressed form. The values in
                      INDX must be distinct for consistent vector or parallel
                      execution.
                      On exit, indx is unchanged.

  y                   real*4 | real*8 | complex*8 | complex*16
                      On entry, an array that receives the scaled elements of
                      the vector x.
                      On exit, if nz <= 0, y is unchanged.  If nz > 0, the
                      elements in the vector y corresponding to the indices
                      in the INDX array are set to the corresponding scaled
                      entries of x.

Description

  The _SCTRS subprograms multiply the elements of a sparse vector x stored in
  compressed form by a scalar alpha and then scatter them into the specified
  elements of the vector y stored in full form.

  For i=1, ..., nz:

  y(indx(i))  =  alpha * x(i)

  If nz <= 0, y is unchanged.

  SSCTRS and DSCTRS scatter the elements of a real sparse vector stored in
  compressed form, after scaling, into the specified elements of a real
  vector stored in full form. CSCTRS and ZSCTRS scatter the elements of a
  complex sparse vector stored in compressed form, after scaling, into the
  specified elements of a complex  vector stored in full form.

  The _SCTRS subprograms are not part of the original set of Sparse BLAS
  Level 1 subprograms.

Example

  INTEGER NZ, INDX(10)
  REAL*8 Y(40), X(10), ALPHA
  NZ = 10
  ALPHA = 2.5D0
  CALL DSCTRS(NZ, ALPHA, X, INDX, Y)

  This FORTRAN code scales the elements of  a  sparse  vector x, stored  in
  compressed  form, by the scalar alpha, and then scatters them into the
  specified elements of the vector  y, stored in full form.

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