?gthr

Gathers a full-storage sparse vector's elements into compressed form.

Syntax

FORTRAN 77:

call sgthr(nz, y, x, indx )

call dgthr(nz, y, x, indx )

call cgthr(nz, y, x, indx )

call zgthr(nz, y, x, indx )

Fortran 95:

res = gthr(x, indx, y)

C:

void cblas_sgthr (const MKL_INT nz, const float *y, float *x, const MKL_INT *indx);

void cblas_dgthr (const MKL_INT nz, const double *y, double *x, const MKL_INT *indx);

void cblas_cgthr (const MKL_INT nz, const void *y, void *x, const MKL_INT *indx);

void cblas_zgthr (const MKL_INT nz, const void *y, void *x, const MKL_INT *indx);

Include Files

  • Fortran: mkl.fi
  • Fortran 95: blas.f90
  • C: mkl.h

Description

The ?gthr routines gather the specified elements of a full-storage sparse vector y into compressed form(nz, x, indx). The routines reference only the elements of y whose indices are listed in the array indx:

x(i) = y(indx(i)), for i=1,2,... ,nz.

Input Parameters

nz

INTEGER. The number of elements of y to be gathered.

indx

INTEGER. Specifies indices of elements to be gathered.

Array, size at least nz.

y

REAL for sgthr

DOUBLE PRECISION for dgthr

COMPLEX for cgthr

DOUBLE COMPLEX for zgthr

Array, size at least max(indx(i)).

Output Parameters

x

REAL for sgthr

DOUBLE PRECISION for dgthr

COMPLEX for cgthr

DOUBLE COMPLEX for zgthr

Array, size at least nz.

Contains the vector converted to the compressed form.

Fortran 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 Fortran 95 Interface Conventions.

Specific details for the routine gthr 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.

For more complete information about compiler optimizations, see our Optimization Notice.