pro reader, filename, nrow, x, y

if n_params() ne 4 then begin
  print, 'You need to supply the filename, the number of rows, and'
  print, '2 variables that will receive the arrays'
  print, string(7B)
  print, ' '
  return
endif 

a = fltarr(2,nrow)

openr,2,filename
readf,2,a
close,2

x=a(0,*)
y=a(1,*)
return
end