stpt01.f3

!>
!> STPT01 computes the residual for a triangular matrix A times its
!> inverse when A is stored in packed format:
!>    RESID = norm(A*AINV - I) / ( N * norm(A) * norm(AINV) * EPS ),
!> where EPS is the machine epsilon.
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the matrix A is upper or lower triangular.
!>          = 'U':  Upper triangular
!>          = 'L':  Lower triangular
!> 

DIAG

!>          DIAG is CHARACTER*1
!>          Specifies whether or not the matrix A is unit triangular.
!>          = 'N':  Non-unit triangular
!>          = 'U':  Unit triangular
!> 

N

!>          N is INTEGER
!>          The order of the matrix A.  N >= 0.
!> 

AP

!>          AP is REAL array, dimension (N*(N+1)/2)
!>          The original upper or lower triangular matrix A, packed
!>          columnwise in a linear array.  The j-th column of A is stored
!>          in the array AP as follows:
!>          if UPLO = 'U', AP((j-1)*j/2 + i) = A(i,j) for 1<=i<=j;
!>          if UPLO = 'L',
!>             AP((j-1)*(n-j) + j*(j+1)/2 + i-j) = A(i,j) for j<=i<=n.
!> 

AINVP

!>          AINVP is REAL array, dimension (N*(N+1)/2)
!>          On entry, the (triangular) inverse of the matrix A, packed
!>          columnwise in a linear array as in AP.
!>          On exit, the contents of AINVP are destroyed.
!> 

RCOND

!>          RCOND is REAL
!>          The reciprocal condition number of A, computed as
!>          1/(norm(A) * norm(AINV)).
!> 

WORK

!>          WORK is REAL array, dimension (N)
!> 

RESID

!>          RESID is REAL
!>          norm(A*AINV - I) / ( N * norm(A) * norm(AINV) * EPS )
!> 

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