drotg (3p)

Name

drotg - Construct a Given's plane rotation

Synopsis

SUBROUTINE DROTG(A, B, C, S)

DOUBLE PRECISION A, B, C, S

SUBROUTINE DROTG_64(A, B, C, S)

DOUBLE PRECISION A, B, C, S




F95 INTERFACE
SUBROUTINE ROTG(A, B, C, S)

REAL(8) :: A, B, C, S

SUBROUTINE ROTG_64(A, B, C, S)

REAL(8) :: A, B, C, S




C INTERFACE
#include <sunperf.h>

void drotg(double *a, double *b, double *c, double *s);

void drotg_64(double *a, double *b, double *c, double *s);

Description

Oracle Solaris Studio Performance Library                            drotg(3P)



NAME
       drotg - Construct a Given's plane rotation


SYNOPSIS
       SUBROUTINE DROTG(A, B, C, S)

       DOUBLE PRECISION A, B, C, S

       SUBROUTINE DROTG_64(A, B, C, S)

       DOUBLE PRECISION A, B, C, S




   F95 INTERFACE
       SUBROUTINE ROTG(A, B, C, S)

       REAL(8) :: A, B, C, S

       SUBROUTINE ROTG_64(A, B, C, S)

       REAL(8) :: A, B, C, S




   C INTERFACE
       #include <sunperf.h>

       void drotg(double *a, double *b, double *c, double *s);

       void drotg_64(double *a, double *b, double *c, double *s);



PURPOSE
       drotg  Construct  a Given's plane rotation that will annihilate an ele-
       ment of a vector.


ARGUMENTS
       A (input/output)
                 On entry, A contains the entry in the first vector that  cor-
                 responds  to the element to be annihilated in the second vec-
                 tor.  On exit, contains the nonzero element  of  the  rotated
                 vector.


       B (input/output)
                 On  entry, B contains the entry to be annihilated in the sec-
                 ond vector.  On exit, contains either S or 1/C  depending  on
                 which of the input values of A and B is larger.


       C (output)
                 On exit, C and S are the elements of the rotation matrix that
                 will be applied to annihilate B.


       S (output)
                 See the description of C.




                                  7 Nov 2015                         drotg(3P)