integer function kf0(x,n,m,k,jmin,jmax)
c
c kf0: index of the maximum of relative_max(x(i,k));  jmin <= i <= jmax
c      [ dimenion of x : n,m ]
c a.tento 5/2003 v.1.0
c
        implicit none
        integer  n, m, k, jmin, jmax
        real x
        dimension x(n,m)
c
        integer i, j
        real p
c
        j = jmin
        p = -1.0e+20
        do 1 i = jmin + 1, jmax - 1
         if ( x(i,k) .gt. p ) then
           if ( x(i,k) .gt. x(i-1,k)  .and.  x(i,k) .ge. x(i+1,k) ) then
            p = x(i,k)
            j = i
           endif
         endif
1       continue
c
        kf0 = j
c
        return
c
c
        end