! C06PYF Example Program Text ! Mark 24 Release. NAG Copyright 2012. Module c06pyfe_mod ! C06PYF Example Program Module: ! Parameters and User-defined Routines ! .. Use Statements .. Use nag_library, Only: nag_wp ! .. Implicit None Statement .. Implicit None ! .. Parameters .. Integer, Parameter :: nin = 5, nout = 6 Contains Subroutine readx(nin,x,n1,n2,n3) ! Read 3-dimensional real data ! .. Scalar Arguments .. Integer, Intent (In) :: n1, n2, n3, nin ! .. Array Arguments .. Real (Kind=nag_wp), Intent (Out) :: x(n1,n2,n3) ! .. Local Scalars .. Integer :: i, j, k ! .. Executable Statements .. Do i = 1, n1 Do j = 1, n2 Read (nin,*)(x(i,j,k),k=1,n3) End Do End Do Return End Subroutine readx Subroutine writx(nout,x,n1,n2,n3) ! Print 3-dimensional real data ! .. Scalar Arguments .. Integer, Intent (In) :: n1, n2, n3, nout ! .. Array Arguments .. Real (Kind=nag_wp), Intent (In) :: x(n1,n2,n3) ! .. Local Scalars .. Integer :: i, j, k ! .. Executable Statements .. Do i = 1, n1 Write (nout,*) Write (nout,99998) 'x(i,j,k) for i =', i Do j = 1, n2 Write (nout,*) Write (nout,99999) 'Real ', (x(i,j,k),k=1,n3) End Do End Do Return 99999 Format (1X,A,4F10.3) 99998 Format (1X,A,I6) End Subroutine writx Subroutine writy(nout,y,n1,n2,n3) ! Print 3-dimensional complex data ! .. Scalar Arguments .. Integer, Intent (In) :: n1, n2, n3, nout ! .. Array Arguments .. Complex (Kind=nag_wp), Intent (In) :: y(n1,n2,n3) ! .. Local Scalars .. Integer :: i, j, k ! .. Intrinsic Procedures .. Intrinsic :: aimag, real ! .. Executable Statements .. Do i = 1, n1 Write (nout,*) Write (nout,99998) 'y(i,j,k) for i =', i Do j = 1, n2 Write (nout,*) Write (nout,99999) 'Real ', (real(y(i,j,k)),k=1,n3) Write (nout,99999) 'Imag ', (aimag(y(i,j,k)),k=1,n3) End Do End Do Return 99999 Format (1X,A,4F10.3) 99998 Format (1X,A,I6) End Subroutine writy End Module c06pyfe_mod Program c06pyfe ! C06PYF Example Main Program ! .. Use Statements .. Use nag_library, Only: c06pyf, c06pzf, nag_wp Use c06pyfe_mod, Only: nin, nout, readx, writx, writy ! .. Implicit None Statement .. Implicit None ! .. Local Scalars .. Integer :: ieof, ifail, n1, n2, n3 ! .. Local Arrays .. Complex (Kind=nag_wp), Allocatable :: y(:) Real (Kind=nag_wp), Allocatable :: x(:) ! .. Executable Statements .. Write (nout,*) 'C06PYF Example Program Results' ! Skip heading in data file Read (nin,*) loop: Do Read (nin,*,Iostat=ieof) n1, n2, n3 If (ieof<0) Exit loop Allocate (x(n1*n2*n3),y((n1/2+1)*n2*n3)) Call readx(nin,x,n1,n2,n3) Write (nout,*) Write (nout,*) 'Original data values' Call writx(nout,x,n1,n2,n3) ! ifail: behaviour on error exit ! =0 for hard exit, =1 for quiet-soft, =-1 for noisy-soft ifail = 0 ! -- Compute transform Call c06pyf(n1,n2,n3,x,y,ifail) Write (nout,*) Write (nout,*) 'Components of discrete Fourier transform' Call writy(nout,y,n1/2+1,n2,n3) ! -- Compute inverse transform x = 0._nag_wp Call c06pzf(n1,n2,n3,y,x,ifail) Write (nout,*) Write (nout,*) 'Original sequence as restored by inverse transform' Call writx(nout,x,n1,n2,n3) Deallocate (x,y) End Do loop End Program c06pyfe