drotm.f man page

drotm.f —

Synopsis

Functions/Subroutines

subroutine drotm (N, DX, INCX, DY, INCY, DPARAM)
DROTM

Function/Subroutine Documentation

subroutine drotm (integerN, double precision, dimension(*)DX, integerINCX, double precision, dimension(*)DY, integerINCY, double precision, dimension(5)DPARAM)

DROTM Purpose:

APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX

(DX**T) , WHERE **T INDICATES TRANSPOSE. THE ELEMENTS OF DX ARE IN
(DY**T)

DX(LX+I*INCX), I = 0 TO N-1, WHERE LX = 1 IF INCX .GE. 0, ELSE
LX = (-INCX)*N, AND SIMILARLY FOR SY USING LY AND INCY.
WITH DPARAM(1)=DFLAG, H HAS ONE OF THE FOLLOWING FORMS..

DFLAG=-1.D0     DFLAG=0.D0        DFLAG=1.D0     DFLAG=-2.D0

  (DH11  DH12)    (1.D0  DH12)    (DH11  1.D0)    (1.D0  0.D0)
H=(          )    (          )    (          )    (          )
  (DH21  DH22),   (DH21  1.D0),   (-1.D0 DH22),   (0.D0  1.D0).
SEE DROTMG FOR A DESCRIPTION OF DATA STORAGE IN DPARAM.

Parameters:

N

 N is INTEGER
number of elements in input vector(s)

DX

 DX is DOUBLE PRECISION array, dimension N
double precision vector with N elements

INCX

 INCX is INTEGER
storage spacing between elements of DX

DY

 DY is DOUBLE PRECISION array, dimension N
double precision vector with N elements

INCY

 INCY is INTEGER
storage spacing between elements of DY

DPARAM

     DPARAM is DOUBLE PRECISION array, dimension 5
DPARAM(1)=DFLAG
DPARAM(2)=DH11
DPARAM(3)=DH21
DPARAM(4)=DH12
DPARAM(5)=DH22

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 99 of file drotm.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

drotm(3) is an alias of drotm.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK