NAG Library Manual, Mark 30.1
Interfaces:  FL   CL   CPP   AD 

NAG FL Interface Introduction
Example description
    Program g03dbfe

!     G03DBF Example Program Text

!     Mark 30.1 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: g03daf, g03dbf, nag_wp, x04caf
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: df, sig, stat
      Integer                          :: i, ifail, ldd, ldgmn, ldox, ldx,     &
                                          lgc, lwk, lwt, m, n, ng, nobs, nvar
      Character (1)                    :: equal, mode, weight
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: d(:,:), det(:), gc(:), gmn(:,:),     &
                                          ox(:,:), wk(:), wt(:), x(:,:)
      Integer, Allocatable             :: ing(:), isx(:), iwk(:), nig(:)
!     .. Intrinsic Procedures ..
      Intrinsic                        :: count, max
!     .. Executable Statements ..
      Write (nout,*) 'G03DBF Example Program Results'
      Write (nout,*)
      Flush (nout)

!     Skip headings in data file
      Read (nin,*)

!     Read in the problem size
      Read (nin,*) n, m, ng, weight

      If (weight=='W' .Or. weight=='w') Then
        lwt = n
      Else
        lwt = 0
      End If
      ldox = n
      Allocate (ox(ldox,m),ing(n),wt(lwt),isx(m))

!     Read in original data
      If (lwt>0) Then
        Read (nin,*)(ox(i,1:m),ing(i),wt(i),i=1,n)
      Else
        Read (nin,*)(ox(i,1:m),ing(i),i=1,n)
      End If

!     Read in variable inclusion flags
      Read (nin,*) isx(1:m)

!     Calculate NVAR
      nvar = count(isx(1:m)==1)

      ldgmn = ng
      lgc = (ng+1)*nvar*(nvar+1)/2
      lwk = max(n*(nvar+1),2*nvar)
      Allocate (nig(ng),gmn(ldgmn,nvar),det(ng),gc(lgc),wk(lwk),iwk(ng))

!     Compute covariance matrix
      ifail = 0
      Call g03daf(weight,n,m,ox,ldox,isx,nvar,ing,ng,wt,nig,gmn,ldgmn,det,gc,  &
        stat,df,sig,wk,iwk,ifail)

!     Read in size data from which to compute distances
      Read (nin,*) mode, equal

      If (mode=='S' .Or. mode=='s') Then
        Read (nin,*) nobs
        ldd = nobs
      Else
        nobs = 0
        ldd = ng
      End If

      ldx = nobs
      Allocate (x(ldx,m),d(ldd,ng))

!     Read in data from which to compute distances
      If (nobs>0) Then
        Read (nin,*)(x(i,1:m),i=1,nobs)
      End If

!     Compute distances
      ifail = 0
      Call g03dbf(equal,mode,nvar,ng,gmn,ldgmn,gc,nobs,m,isx,x,ldx,d,ldd,wk,   &
        ifail)

!     Display results
      ifail = 0
      Call x04caf('General',' ',nobs,ng,d,ldd,'Distances',ifail)

    End Program g03dbfe