Can I draw a graph without giving "node_x" and "node_y" values? (show_graph)

["Rémi G."]

Hello!

If I define a graph :
  g = make_graph('toto',0,3,[1,2,3],[2,3,1])
And I want to draw it :
  show_graph(g)

I get many errors begining with (I don't know how to copy/past from 
scilab interpretor output) :
  !-- error 60
  argument with incompatible dimensions
  ...

This error seems to come from the lack of "node_x" and "node_y" value... 
Nevertheless, I saw in the graph-list help page that these values are 
computed by default!
Could you help on this matter?

Rémi.