; performs 1D integration between 2 points
; interactively determined

if ($dim != 1) error "in 1D only"
point
if ($npoint !=2) error "you must click twice"
set ii = 0
for i = (min($pointx[1],$pointx[2])) to (max($pointx[1],$pointx[2]))
  set ii = ($ii + val1d($i) )
endfor
showtext $ii ($pointx[1] + ($pointx[2]-$pointx[1])/2)  80 
print ("From";$pointx[1];"to";$pointx[2];"(";1+abs($pointx[2]-$pointx[1]);"points) :";$ii)
