# Re: Calling plotutils from xemacs using Ruby GSL **URL:** \ **Category:** Ruby\ **Created:** [March 12, 2006, 2:41pm UTC](https://www.ruby-forum.com/t/re-calling-plotutils-from-xemacs-using-ruby-gsl/80094 "2006-03-12T14:41:30Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\ **Post date:** [March 12, 2006, 2:41pm UTC](https://www.ruby-forum.com/t/re-calling-plotutils-from-xemacs-using-ruby-gsl/80094/1 "2006-03-12T14:41:30Z")
Sorry, I actually wanted to say something else in my last mail, letting you try > ruby rnd3.rb | graph -Tps \> g.ps , which works out for me. It sends the results from ruby to the external GNU program “graph” , which is part of the plotutils package. I can then open the file g.ps with ghostscript (gv,ggv or whatever). The errors NameError: uninitialized constant RND etc… you reported come from the fact that Ruby does not know what these constants are, and after some digging into the description of rb-gsl, I found out that there are two ways of requiring rb-gsl, require “rbgsl” or require “gsl”, one of these forms lets you drop everything before the ‘::’ , so you can use a=dir\_2d® instead of a = RND::dir\_2d® . Maybe the author changed his mind on which form of require to associate with which form in between… But I still am not able to run the first program you posted, either, where I also get the error graph([x,y], [roots.real,zero], “-T X -C -g 3 -S 4”) NoMethodError: GNU plotutils required from (irb):7:in `graph’ from (irb):7 you reported. I do not know how to fix this directly, but for me, it worked out to patch that by piping the results of a ruby program into graph as above. Sorry I can’t help any further -maybe more experienced users of plotting with plotutils under rb-gsl are willing to help out ? Best regards, Axel