drotg(3P)
NAME
drotg - Construct a Given’s plane rotation
SYNOPSIS
SUBROUTINE DROTG (A, B, C, S)
DOUBLE PRECISION A, B, C, S
#include <sunperf.h>
void drotg(double ∗da, double ∗db, double ∗dc, double ∗s) ;
PURPOSE
DROTG - Construct a Given’s plane rotation that will annihilate an element of a vector.
PARAMETERS
A - DOUBLE PRECISION.
On entry, A contains the entry in the first vector that corresponds to the element to be annihilated in the second vector. Unchanged on exit.
B - DOUBLE PRECISION.
On entry, B contains the entry to be annihilated in the second vector. Unchanged on exit.
C, S - DOUBLE PRECISION. On exit, C and S are the elements of the rotation matrix that will be applied to annihilate B.
SunOS 5.0 — Last change: 10 Dec 1998