ZPTT01 reconstructs a tridiagonal matrix A from its L*D*L'


 factorization and computes the residual


    norm(L*D*L' - A) / ( n * norm(A) * EPS ),


 where EPS is the machine epsilon.

N

          N is INTEGER


          The order of the matrix A.

D

          D is DOUBLE PRECISION array, dimension (N)


          The n diagonal elements of the tridiagonal matrix A.

E

          E is COMPLEX*16 array, dimension (N-1)


          The (n-1) subdiagonal elements of the tridiagonal matrix A.

DF

          DF is DOUBLE PRECISION array, dimension (N)


          The n diagonal elements of the factor L from the L*D*L'


          factorization of A.

EF

          EF is COMPLEX*16 array, dimension (N-1)


          The (n-1) subdiagonal elements of the factor L from the


          L*D*L' factorization of A.

WORK

          WORK is COMPLEX*16 array, dimension (2*N)

RESID

          RESID is DOUBLE PRECISION


          norm(L*D*L' - A) / (n * norm(A) * EPS)

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