subroutine minimum (ddist2, irmax, ichoice, dmin)
	dimension ddist2(500)

	dmin = 100000
	do 9000 i = 1, irmax
	  if (ddist2(i).lt.dmin) then
	    dmin = ddist2(i)
	    ichoice = i
	  endif
c	end do
9000	continue
	return
	end

c---------------------------------------------------