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dlar2v

 NAME
      DLAR2V - apply 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.