CLATSY generates a special test matrix for the complex symmetric


 (indefinite) factorization.  The pivot blocks of the generated matrix


 will be in the following order:


    2x2 pivot block, non diagonalizable


    1x1 pivot block


    2x2 pivot block, diagonalizable


    (cycle repeats)


 A row interchange is required for each non-diagonalizable 2x2 block.

UPLO

          UPLO is CHARACTER


          Specifies whether the generated matrix is to be upper or


          lower triangular.


          = 'U':  Upper triangular


          = 'L':  Lower triangular

N

          N is INTEGER


          The dimension of the matrix to be generated.

X

          X is COMPLEX array, dimension (LDX,N)


          The generated matrix, consisting of 3x3 and 2x2 diagonal


          blocks which result in the pivot sequence given above.


          The matrix outside of these diagonal blocks is zero.

LDX

          LDX is INTEGER


          The leading dimension of the array X.

ISEED

          ISEED is INTEGER array, dimension (4)


          On entry, the seed for the random number generator.  The last


          of the four integers must be odd.  (modified on exit)

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