NAME¶

DLAR2V - applies a vector of real plane rotations from both sides to a sequence of 2-by-2 real symmetric matrices, defined by the elements of the vectors x, y and z

SYNOPSIS¶

SUBROUTINE DLAR2V(

N, X, Y, Z, INCX, C, S, INCC )

INTEGER INCC, INCX, N DOUBLE PRECISION C( * ), S( * ), X( * ), Y( * ), Z( * )

PURPOSE¶

DLAR2V applies a vector of real plane rotations from both sides to a sequence of 2-by-2 real symmetric matrices, defined by the elements of the vectors x, y and z. For i = 1,2,...,n
( x(i) z(i) ) := ( c(i) s(i) ) ( x(i) z(i) ) ( c(i) -s(i) )
( z(i) y(i) ) ( -s(i) c(i) ) ( z(i) y(i) ) ( s(i) c(i) )

ARGUMENTS¶

N (input) INTEGER

The number of plane rotations to be applied.

X (input/output) DOUBLE PRECISION array,

dimension (1+(N-1)*INCX) The vector x.

Y (input/output) DOUBLE PRECISION array,

dimension (1+(N-1)*INCX) The vector y.

Z (input/output) DOUBLE PRECISION array,

dimension (1+(N-1)*INCX) The vector z.

INCX (input) INTEGER

The increment between elements of X, Y and Z. INCX > 0.

C (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)

The cosines of the plane rotations.

S (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC)

The sines of the plane rotations.

INCC (input) INTEGER

The increment between elements of C and S. INCC > 0.