R1MPYQ(3)

SYNOPSIS
SUBROUTINE R1MPYQ (M, N, A, LDA, V, W)

NAME
r1mpyq - Subsidiary to SNSQ and SNSQE

LIBRARY
SLATEC

TYPE
SINGLE PRECISION (R1MPYQ-S, D1MPYQ-D)

AUTHOR
(UNKNOWN)

DESCRIPTION
Given an M by N matrix A, this subroutine computes A*Q where Q is the product of 2*(N - 1) transformations GV(N-1)*...*GV(1)*GW(1)*...*GW(N-1) and GV(I), GW(I) are Givens rotations in the (I,N) plane which eliminate elements in the I-th and N-th planes, respectively. Q itself is not given, rather the information to recover the GV, GW rotations is supplied. The subroutine statement is SUBROUTINE R1MPYQ(M,N,A,LDA,V,W) where M is a positive integer input variable set to the number of rows of A. N is a positive integer input variable set to the number of columns of A. A is an M by N ARRAY. On input A must contain the matrix to be postmultiplied by the orthogonal matrix Q described above. On output A*Q has replaced A. LDA is a positive integer input variable not less than M which specifies the leading dimension of the array A. V is an input array of length N. V(I) must contain the information necessary to recover the Givens rotation GV(I) described above. W is an input array of length N. W(I) must contain the information necessary to recover the Givens rotation GW(I) described above.

SEE ALSO
SNSQ, SNSQE

ROUTINES CALLED
(NONE)

REVISION HISTORY (YYMMDD)
800301 DATE WRITTEN
890831 Modified array declarations. (WRB)
891214 Prologue converted to Version 4.0 format. (BAB)
900326 Removed duplicate information from DESCRIPTION section. (WRB)
900328 Added TYPE section. (WRB)