cblas_?roti
cblas_?roti
Applies Givens rotation to sparse vectors one of which is in compressed form.
Syntax
void
cblas_sroti
(
const
MKL_INT
nz
,
float
*x
,
const
MKL_INT
*indx
,
float
*y
,
const
float
c
,
const
float
s
);
void
cblas_droti
(
const
MKL_INT
nz
,
double
*x
,
const
MKL_INT
*indx
,
double
*y
,
const
double
c
,
const
double
s
);
Include Files
- mkl.h
Description
The
?roti
routines apply the Givens rotation to elements of two real vectors, x
(in compressed form nz
, x
, indx
) and y
(in full storage form):x[i] = c*x[i] + s*y[indx[i]]
y[indx[i]] = c*y[indx[i]]- s*x[i]
The routines reference only the elements of
y
whose indices are listed in the array indx
. The values in indx
must be distinct.Input Parameters
- nz
- The number of elements inxandindx.
- x
- Array, size at leastnz.
- indx
- Specifies the indices for the elements ofx.Array, size at leastnz.
- y
- Array, size at least max(indx[i]).
- c
- A scalar.
- s
- A scalar.
Output Parameters
- xandy
- The updated arrays.