PROGRAM c06pqfe ! C06PQF Example Program Text ! Mark 23 Release. NAG Copyright 2011. ! .. Use Statements .. USE nag_library, ONLY : c06pqf, nag_wp ! .. Implicit None Statement .. IMPLICIT NONE ! .. Parameters .. INTEGER, PARAMETER :: nin = 5, nout = 6 ! .. Local Scalars .. INTEGER :: i, ieof, ifail, j, m, n ! .. Local Arrays .. REAL (KIND=nag_wp), ALLOCATABLE :: work(:), x(:) ! .. Executable Statements .. WRITE (nout,*) 'C06PQF Example Program Results' ! Skip heading in data file READ (nin,*) LOOP: DO READ (nin,*,IOSTAT=ieof) m, n IF (ieof<0) EXIT LOOP ALLOCATE (work((m+2)*n+15),x(m*(n+2))) DO j = 1, m*(n+2), n + 2 READ (nin,*) (x(j+i),i=0,n-1) END DO WRITE (nout,*) WRITE (nout,*) 'Original data values' WRITE (nout,*) DO j = 1, m*(n+2), n + 2 WRITE (nout,99999) ' ', (x(j+i),i=0,n-1) END DO ! ifail: behaviour on error exit ! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft ifail = 0 CALL c06pqf('F',n,m,x,work,ifail) WRITE (nout,*) WRITE (nout,*) & 'Discrete Fourier transforms in complex Hermitian format' DO j = 1, m*(n+2), n + 2 WRITE (nout,*) WRITE (nout,99999) 'Real ', (x(j+2*i),i=0,n/2) WRITE (nout,99999) 'Imag ', (x(j+2*i+1),i=0,n/2) END DO WRITE (nout,*) WRITE (nout,*) 'Fourier transforms in full complex form' DO j = 1, m*(n+2), n + 2 WRITE (nout,*) WRITE (nout,99999) 'Real ', (x(j+2*i),i=0,n/2), & (x(j+2*(n-i)),i=n/2+1,n-1) WRITE (nout,99999) 'Imag ', (x(j+2*i+1),i=0,n/2), & (-x(j+2*(n-i)+1),i=n/2+1,n-1) END DO CALL c06pqf('B',n,m,x,work,ifail) WRITE (nout,*) WRITE (nout,*) 'Original data as restored by inverse transform' WRITE (nout,*) DO j = 1, m*(n+2), n + 2 WRITE (nout,99999) ' ', (x(j+i),i=0,n-1) END DO DEALLOCATE (x,work) END DO LOOP 99999 FORMAT (1X,A,9(:1X,F10.4)) END PROGRAM c06pqfe