PROGRAM f07ugfe ! F07UGF Example Program Text ! Mark 23 Release. NAG Copyright 2011. ! .. Use Statements .. USE nag_library, ONLY : dtpcon, nag_wp, x02ajf ! .. Implicit None Statement .. IMPLICIT NONE ! .. Parameters .. INTEGER, PARAMETER :: nin = 5, nout = 6 CHARACTER (1), PARAMETER :: diag = 'N', norm = '1' ! .. Local Scalars .. REAL (KIND=nag_wp) :: rcond INTEGER :: i, info, j, n CHARACTER (1) :: uplo ! .. Local Arrays .. REAL (KIND=nag_wp), ALLOCATABLE :: ap(:), work(:) INTEGER, ALLOCATABLE :: iwork(:) ! .. Executable Statements .. WRITE (nout,*) 'F07UGF Example Program Results' ! Skip heading in data file READ (nin,*) READ (nin,*) n ALLOCATE (ap(n*(n+1)/2),work(3*n),iwork(n)) ! Read A from data file READ (nin,*) uplo IF (uplo=='U') THEN READ (nin,*) ((ap(i+j*(j-1)/2),j=i,n),i=1,n) ELSE IF (uplo=='L') THEN READ (nin,*) ((ap(i+(2*n-j)*(j-1)/2),j=1,i),i=1,n) END IF ! Estimate condition number ! The NAG name equivalent of dtpcon is f07ugf CALL dtpcon(norm,uplo,diag,n,ap,rcond,work,iwork,info) WRITE (nout,*) IF (rcond>=x02ajf()) THEN WRITE (nout,99999) 'Estimate of condition number =', & 1.0E0_nag_wp/rcond ELSE WRITE (nout,*) 'A is singular to working precision' END IF 99999 FORMAT (1X,A,1P,E10.2) END PROGRAM f07ugfe