SPOT03 computes the residual for a symmetric matrix times its


 inverse:


    norm( I - A*AINV ) / ( N * norm(A) * norm(AINV) * EPS ),


 where EPS is the machine epsilon.

UPLO

          UPLO is CHARACTER*1


          Specifies whether the upper or lower triangular part of the


          symmetric 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 REAL array, dimension (LDA,N)


          The original symmetric matrix A.

LDA

          LDA is INTEGER


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

AINV

          AINV is REAL array, dimension (LDAINV,N)


          On entry, the inverse of the matrix A, stored as a symmetric


          matrix in the same format as A.


          In this version, AINV is expanded into a full matrix and


          multiplied by A, so the opposing triangle of AINV will be


          changed; i.e., if the upper triangular part of AINV is


          stored, the lower triangular part will be used as work space.

LDAINV

          LDAINV is INTEGER


          The leading dimension of the array AINV.  LDAINV >= max(1,N).

WORK

          WORK is REAL array, dimension (LDWORK,N)

LDWORK

          LDWORK is INTEGER


          The leading dimension of the array WORK.  LDWORK >= max(1,N).

RWORK

          RWORK is REAL array, dimension (N)

RCOND

          RCOND is REAL


          The reciprocal of the condition number of A, computed as


          ( 1/norm(A) ) / norm(AINV).

RESID

          RESID is REAL


          norm(I - A*AINV) / ( N * norm(A) * norm(AINV) * EPS )

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