CPST01 reconstructs an Hermitian positive semidefinite matrix A


 from its L or U factors and the permutation matrix P and computes


 the residual


    norm( P*L*L'*P' - A ) / ( N * norm(A) * EPS ) or


    norm( P*U'*U*P' - A ) / ( N * norm(A) * EPS ),


 where EPS is the machine epsilon, L' is the conjugate transpose of L,


 and U' is the conjugate transpose of U.

UPLO

          UPLO is CHARACTER*1


          Specifies whether the upper or lower triangular part of the


          Hermitian matrix A is stored:


          = 'U':  Upper triangular


          = 'L':  Lower triangular

N

          N is INTEGER


          The number of rows and columns of the matrix A.  N >= 0.

A

          A is COMPLEX array, dimension (LDA,N)


          The original Hermitian matrix A.

LDA

          LDA is INTEGER


          The leading dimension of the array A.  LDA >= max(1,N)

AFAC

          AFAC is COMPLEX array, dimension (LDAFAC,N)


          The factor L or U from the L*L' or U'*U


          factorization of A.

LDAFAC

          LDAFAC is INTEGER


          The leading dimension of the array AFAC.  LDAFAC >= max(1,N).

PERM

          PERM is COMPLEX array, dimension (LDPERM,N)


          Overwritten with the reconstructed matrix, and then with the


          difference P*L*L'*P' - A (or P*U'*U*P' - A)

LDPERM

          LDPERM is INTEGER


          The leading dimension of the array PERM.


          LDAPERM >= max(1,N).

PIV

          PIV is INTEGER array, dimension (N)


          PIV is such that the nonzero entries are


          P( PIV( K ), K ) = 1.

RWORK

          RWORK is REAL array, dimension (N)

RESID

          RESID is REAL


          If UPLO = 'L', norm(L*L' - A) / ( N * norm(A) * EPS )


          If UPLO = 'U', norm(U'*U - A) / ( N * norm(A) * EPS )

RANK

          RANK is INTEGER


          number of nonzero singular values of A.

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