! G05ZSF Example Program Text
! Mark 26.1 Release. NAG Copyright 2016.
Program g05zsfe
! G05ZSF Example Main Program
! .. Use Statements ..
Use nag_library, Only: g05zrf, g05zsf, nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: lenst = 17, nin = 5, nout = 6, &
npmax = 4
! .. Local Scalars ..
Real (Kind=nag_wp) :: rho, var, xmax, xmin, ymax, ymin
Integer :: approx, icorr, icount, icov2, ifail, &
norm, np, pad, s
! .. Local Arrays ..
Real (Kind=nag_wp) :: eig(3), params(npmax)
Real (Kind=nag_wp), Allocatable :: lam(:), xx(:), yy(:), z(:,:)
Integer :: m(2), maxm(2), ns(2), state(lenst)
! .. Executable Statements ..
Write (nout,*) 'G05ZSF Example Program Results'
Write (nout,*)
Flush (nout)
! Get problem specifications from data file
Call read_input_data(icov2,np,params,norm,var,xmin,xmax,ymin,ymax,ns, &
maxm,icorr,pad,s)
Allocate (lam(maxm(1)*maxm(2)),xx(ns(1)),yy(ns(2)))
! Get square roots of the eigenvalues of the embedding matrix
ifail = 0
Call g05zrf(ns,xmin,xmax,ymin,ymax,maxm,var,icov2,norm,np,params,pad, &
icorr,lam,xx,yy,m,approx,rho,icount,eig,ifail)
Call display_embedding_results(approx,m,rho,eig,icount)
! Initialize state array
Call initialize_state(state)
Allocate (z(ns(1)*ns(2),s))
! Compute s random field realizations
ifail = 0
Call g05zsf(ns,s,m,lam,rho,state,z,ifail)
Call display_realizations(ns,s,xx,yy,z)
Contains
Subroutine read_input_data(icov2,np,params,norm,var,xmin,xmax,ymin,ymax, &
ns,maxm,icorr,pad,s)
! .. Implicit None Statement ..
Implicit None
! .. Scalar Arguments ..
Real (Kind=nag_wp), Intent (Out) :: var, xmax, xmin, ymax, ymin
Integer, Intent (Out) :: icorr, icov2, norm, np, pad, s
! .. Array Arguments ..
Real (Kind=nag_wp), Intent (Out) :: params(npmax)
Integer, Intent (Out) :: maxm(2), ns(2)
! .. Executable Statements ..
! Skip heading in data file
Read (nin,*)
! Read in covariance function number
Read (nin,*) icov2
! Read in number of parameters
Read (nin,*) np
! Read in parameters
If (np>0) Then
Read (nin,*) params(1:np)
End If
! Read in choice of norm to use
Read (nin,*) norm
! Read in variance of random field
Read (nin,*) var
! Read in domain endpoints
Read (nin,*) xmin, xmax
Read (nin,*) ymin, ymax
! Read in number of sample points
Read (nin,*) ns(1:2)
! Read in maximum size of embedding matrix
Read (nin,*) maxm(1:2)
! Read in choice of scaling in case of approximation
Read (nin,*) icorr
! Read in choice of padding
Read (nin,*) pad
! Read in number of realization samples to be generated
Read (nin,*) s
Return
End Subroutine read_input_data
Subroutine display_embedding_results(approx,m,rho,eig,icount)
! .. Implicit None Statement ..
Implicit None
! .. Scalar Arguments ..
Real (Kind=nag_wp), Intent (In) :: rho
Integer, Intent (In) :: approx, icount
! .. Array Arguments ..
Real (Kind=nag_wp), Intent (In) :: eig(3)
Integer, Intent (In) :: m(2)
! .. Executable Statements ..
! Display size of embedding matrix
Write (nout,*)
Write (nout,99999) 'Size of embedding matrix = ', m(1)*m(2)
! Display approximation information if approximation used
Write (nout,*)
If (approx==1) Then
Write (nout,*) 'Approximation required'
Write (nout,*)
Write (nout,99998) 'RHO = ', rho
Write (nout,99997) 'EIG = ', eig(1:3)
Write (nout,99999) 'ICOUNT = ', icount
Else
Write (nout,*) 'Approximation not required'
End If
Return
99999 Format (1X,A,I7)
99998 Format (1X,A,F10.5)
99997 Format (1X,A,3(F10.5,1X))
End Subroutine display_embedding_results
Subroutine initialize_state(state)
! .. Use Statements ..
Use nag_library, Only: g05kff
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: genid = 1, inseed = 14965, &
lseed = 1, subid = 1
! .. Array Arguments ..
Integer, Intent (Out) :: state(lenst)
! .. Local Scalars ..
Integer :: ifail, lstate
! .. Local Arrays ..
Integer :: seed(lseed)
! .. Executable Statements ..
! Initialize the generator to a repeatable sequence
lstate = lenst
seed(1) = inseed
ifail = 0
Call g05kff(genid,subid,seed,lseed,state,lstate,ifail)
End Subroutine initialize_state
Subroutine display_realizations(ns,s,xx,yy,z)
! .. Use Statements ..
Use nag_library, Only: x04cbf
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: indent = 0, ncols = 80
Character (1), Parameter :: charlab = 'C', intlab = 'I', &
matrix = 'G', unit = 'n'
Character (5), Parameter :: form = 'F10.5'
! .. Scalar Arguments ..
Integer, Intent (In) :: s
! .. Array Arguments ..
Integer, Intent (In) :: ns(2)
Real (Kind=nag_wp), Intent (In) :: xx(ns(1)), yy(ns(2)), &
z(ns(1)*ns(2),s)
! .. Local Scalars ..
Integer :: i, ifail, j, nn
Character (61) :: title
! .. Local Arrays ..
Character (1) :: clabs(0)
Character (12), Allocatable :: rlabs(:)
! .. Executable Statements ..
nn = ns(1)*ns(2)
Allocate (rlabs(nn))
! Set row labels to grid points (column label is realization number).
Do j = 1, ns(2)
Do i = 1, ns(1)
If (i==1) Then
Write (rlabs((j-1)*ns(1)+i),99999) xx(i), yy(j)
Else
Write (rlabs((j-1)*ns(1)+i),99998) xx(i)
End If
End Do
End Do
! Display random field results
title = 'Random field realizations (x,y coordinates first):'
Write (nout,*)
Flush (nout)
ifail = 0
Call x04cbf(matrix,unit,nn,s,z,nn,form,title,charlab,rlabs,intlab, &
clabs,ncols,indent,ifail)
99999 Format (2F6.1)
99998 Format (F6.1,5X,'.')
End Subroutine display_realizations
End Program g05zsfe