Developer Reference

Contents

cblas_?rotg

Computes the parameters for a Givens rotation.

Syntax

void
cblas_srotg
(
float
*a
,
float
*b
,
float
*c
,
float
*s
);
void
cblas_drotg
(
double
*a
,
double
*b
,
double
*c
,
double
*s
);
void
cblas_crotg
(
void
*a
,
const
void
*b
,
float
*c
,
void
*s
);
void
cblas_zrotg
(
void
*a
,
const
void
*b
,
double
*c
,
void
*s
);
Include Files
  • mkl.h
Description
Given the Cartesian coordinates
(
a
,
b
)
of a point,
these
routines return the parameters
c
,
s
,
r
, and
z
associated with the Givens rotation. The parameters
c
and
s
define a unitary matrix such that:
Equation
The parameter
z
is defined such that if |
a
| > |
b
|,
z
is
s
; otherwise if
c
is not 0
z
is 1/
c
; otherwise
z
is 1.
Input Parameters
a
Provides the
x
-coordinate of the point
p
.
b
Provides the
y
-coordinate of the point
p
.
Output Parameters
a
Contains
the parameter
r
associated with the Givens rotation.
b
Contains
the parameter
z
associated with the Givens rotation.
c
Contains
the parameter
c
associated with the Givens rotation.
s
Contains
the parameter
s
associated with the Givens rotation.

Product and Performance Information

1

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