NAG Library Manual, Mark 30.2
Interfaces:  FL   CL   CPP   AD 

NAG FL Interface Introduction
Example description
    Program g08cgfe

!     G08CGF Example Program Text

!     Mark 30.2 Release. NAG Copyright 2024.

!     .. Use Statements ..
      Use nag_library, Only: g01aef, g08cgf, nag_wp
!     .. Implicit None Statement ..
      Implicit None
!     .. Parameters ..
      Integer, Parameter               :: nin = 5, nout = 6
!     .. Local Scalars ..
      Real (Kind=nag_wp)               :: chisq, p, xmax, xmin
      Integer                          :: iclass, ifail, n, nclass, ndf, npar, &
                                          npest
      Character (1)                    :: dist
!     .. Local Arrays ..
      Real (Kind=nag_wp), Allocatable  :: cb(:), chisqi(:), eval(:), prob(:),  &
                                          x(:)
      Real (Kind=nag_wp)               :: par(2)
      Integer, Allocatable             :: ifreq(:)
!     .. Executable Statements ..
      Write (nout,*) 'G08CGF Example Program Results'
      Write (nout,*)

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

!     Read in problem size
      Read (nin,*) n

!     Read in class information
      Read (nin,*) nclass, iclass

      Allocate (x(n),cb(nclass),ifreq(nclass),prob(nclass),eval(nclass),       &
        chisqi(nclass))

!     Read in data
      Read (nin,*) x(1:n)

!     Read in the class boundaries, if supplied
      If (iclass==1) Then
        Read (nin,*) cb(1:(nclass-1))
      End If

!     Read in information on the distribution to test against
      Read (nin,*) dist, npest

      Select Case (dist)
      Case ('A','a')
        npar = 0
      Case ('E','e','C','c')
        npar = 1
      Case Default
        npar = 2
      End Select

!     Read in the distribution parameters or probabilities
      If (npar==0) Then
        Read (nin,*) prob(1:nclass)
      Else
        Read (nin,*) par(1:npar)
      End If

!     Produce frequency table for data
      ifail = 0
      Call g01aef(n,nclass,x,iclass,cb,ifreq,xmin,xmax,ifail)

!     Perform chi-squared test
      ifail = -1
      Call g08cgf(nclass,ifreq,cb,dist,par,npest,prob,chisq,p,ndf,eval,chisqi, &
        ifail)
      If (ifail/=0) Then
        If (ifail<=9) Then
          Go To 100
        End If
      End If

!     Display results
      Write (nout,99999) 'Chi-squared test statistic   = ', chisq
      Write (nout,99998) 'Degrees of freedom.          = ', ndf
      Write (nout,99999) 'Significance level           = ', p
      Write (nout,*)
      Write (nout,*) 'The contributions to the test statistic are :-'
      Write (nout,99997) chisqi(1:nclass)

100   Continue

99999 Format (1X,A,F10.4)
99998 Format (1X,A,I5)
99997 Format (1X,F10.4)
    End Program g08cgfe