Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

  • 2021.1
  • 12/04/2020
  • Public Content
Contents

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 in
x
 and
indx
.
x
Array, size at least
nz
.
indx
Specifies the indices for the elements of
x
.
Array, size at least
nz
.
y
Array, size at least max(
indx[i]
).
c
A scalar.
s
A scalar.
Output Parameters
x
 and
y
The updated arrays.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.