Program g02eafe

!     G02EAF Example Program Text

!     Mark 27.3 Release. NAG Copyright 2021.

!     .. Use Statements ..
      Use nag_library, Only: g02eaf, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6, vnlen = 3
!     .. Local Scalars ..
      Integer                          :: i, ifail, k, ldmodl, ldx, lwt, m, n, &
                                          nmod
      Character (1)                    :: mean, weight
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: rss(:), wk(:), wt(:), x(:,:), y(:)
      Integer, Allocatable             :: isx(:), mrank(:), nterms(:)
      Character (vnlen), Allocatable   :: modl(:,:), vname(:)
!     .. Intrinsic Procedures ..
      Intrinsic                        :: count, max
!     .. Executable Statements ..
      Write (nout,*) 'G02EAF Example Program Results'
      Write (nout,*)

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

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

      If (weight=='W' .Or. weight=='w') Then
        lwt = n
      Else
        lwt = 0
      End If
      ldx = n
      Allocate (x(ldx,m),vname(m),isx(m),y(n),wt(lwt))

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

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

!     Read in first VNLEN characters of the variable names
      Read (nin,*) vname(1:m)

!     Calculate the number of free variables
      k = count(isx(1:m)==1)

      ldmodl = max(m,2**k)
      Allocate (modl(ldmodl,m),rss(ldmodl),nterms(ldmodl),mrank(ldmodl),wk(n*( &
        m+1)))

!     Calculate residual sums of squares for all possible models
      ifail = 0
      Call g02eaf(mean,weight,n,m,x,ldx,vname,isx,y,wt,nmod,modl,ldmodl,rss,   &
        nterms,mrank,wk,ifail)

!     Display results
      Write (nout,*) 'Number of     RSS    RANK  MODL'
      Write (nout,*) 'parameters'
      Do i = 1, nmod
        Write (nout,99999) nterms(i), rss(i), mrank(i), modl(i,1:nterms(i))
      End Do

99999 Format (1X,I8,F11.4,I4,3X,5(1X,A))
    End Program g02eafe