CSROT(3)

SYNOPSIS
SUBROUTINE CSROT (N, CX, INCX, CY, INCY, C, S)

NAME
csrot - Apply a plane Givens rotation.

LIBRARY
SLATEC (BLAS)

CATEGORY
D1B10

TYPE
COMPLEX (SROT-S, DROT-D, CSROT-C)

KEYWORDS
BLAS, GIVENS ROTATION, GIVENS TRANSFORMATION, LINEAR ALGEBRA, PLANE ROTATION, VECTOR

AUTHOR
Dongarra, J., (ANL)

DESCRIPTION
CSROT applies the complex Givens rotation (X) ( C S)(X) (Y) = (-S C)(Y) N times where for I = 0,...,N-1 X = CX(LX+I*INCX) Y = CY(LY+I*INCY), where LX = 1 if INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar way using INCY. Argument Description N (integer) number of elements in each vector CX (complex array) beginning of one vector INCX (integer) memory spacing of successive elements of vector CX CY (complex array) beginning of the other vector INCY (integer) memory spacing of successive elements of vector CY C (real) cosine term of the rotation S (real) sine term of the rotation.

REFERENCES
J. J. Dongarra, J. R. Bunch, C. B. Moler, and G. W. Stewart, LINPACK Users' Guide, SIAM, 1979.

ROUTINES CALLED
(NONE)

REVISION HISTORY (YYMMDD)
810223 DATE WRITTEN
890831 Modified array declarations. (WRB)
890831 REVISION DATE from Version 3.2
891214 Prologue converted to Version 4.0 format. (BAB)
920310 Corrected definition of LX in DESCRIPTION. (WRB)
920501 Reformatted the REFERENCES section. (WRB)