```
Program g08ajfe
! G08AJF Example Program Text
! Mark 26.2 Release. NAG Copyright 2017.
! .. Use Statements ..
Use nag_library, Only: g08ahf, g08ajf, nag_wp
! .. Implicit None Statement ..
Implicit None
! .. Parameters ..
Integer, Parameter :: nin = 5, nout = 6
! .. Local Scalars ..
Real (Kind=nag_wp) :: p, pexact, u, unor
Integer :: ifail, lwrk, lwrk1, lwrk2, n1, n2, &
nsum
Logical :: ties
Character (1) :: tail
! .. Local Arrays ..
Real (Kind=nag_wp), Allocatable :: ranks(:), wrk(:), x(:), y(:)
! .. Intrinsic Procedures ..
Intrinsic :: int, max
! .. Executable Statements ..
Write (nout,*) 'G08AJF Example Program Results'
Write (nout,*)
! Skip heading in data file
Read (nin,*)
! Read in problem size
Read (nin,*) n1, n2, tail
! Calculate sizes of various workspaces
nsum = n1 + n2
! Workspace for G08AHF
lwrk1 = nsum
! Workspace for G08AJF
lwrk2 = int(n1*n2/2) + 1
lwrk = max(lwrk1,lwrk2)
Allocate (x(n1),y(n2),ranks(nsum),wrk(lwrk))
! Read in data
Read (nin,*) x(1:n1)
Read (nin,*) y(1:n2)
! Display title
Write (nout,*) 'Mann-Whitney U test'
Write (nout,*)
! Display input data
Write (nout,99999) 'Sample size of group 1 = ', n1
Write (nout,99999) 'Sample size of group 2 = ', n2
Write (nout,*)
Write (nout,*) 'Data values'
Write (nout,*)
Write (nout,99998) ' Group 1 ', x(1:n1)
Write (nout,*)
Write (nout,99998) ' Group 2 ', y(1:n2)
! Perform test
ifail = 0
Call g08ahf(n1,x,n2,y,tail,u,unor,p,ties,ranks,wrk,ifail)
! Calculate exact probabilities
If (.Not. ties) Then
ifail = 0
Call g08ajf(n1,n2,tail,u,pexact,wrk,lwrk,ifail)
End If
! Display results
Write (nout,*)
Write (nout,99997) 'Test statistic = ', u
Write (nout,99997) 'Normal statistic = ', unor
Write (nout,99997) 'Tail probability = ', p
Write (nout,*)
If (.Not. ties) Then
Write (nout,99997) 'Exact tail probability = ', pexact
Else
Write (nout,*) &
'There are ties in the pooled sample so G08AJF was not called.'
End If
99999 Format (1X,A,I5)
99998 Format (1X,A,8F5.1,2(/,14X,8F5.1))
99997 Format (1X,A,F10.4)
End Program g08ajfe
```