Static variables

Rails
1

Hi
In controller I have
def role_wise_summary_graph_render
@graph1 = open_flash_chart_object(300,200,
“#{summary_graph_path(:role_name => ‘Role1’)}”, true)
@graph2 = open_flash_chart_object(300,200,
“#{summary_graph_path(:role_name => ‘Role2’)}”, true)
respond_to do |format|

    end

end

###summary_graph_path => :action => draw_role_level_summary_graph
def draw_role_level_summary_graph

@role1_array,@role2_array,@open_requests =
MyRequest.get_role_wise_summary_graph_data

if params[:role_name] == 'Role1'
  role_data_array = @role1_array
elsif params[:role_name] == 'Role2'
  role_data_array = @role2_array
end
 graph =

role_level_graph(params[:role_name],role_data_array,@open_requests)
render :text => graph.render
end

Here in above role_level_graph is a library function finally

responsible for drawing graph The above code is working
My question is in the above how can I make the varibales
@role1_array,@role2_array,@open_requests static so that only once
MyRequest.get_role_wise_summary_graph_data get called Because I need it
only once But happens now is all the two times this def gets called How
can I avoid this to call this only once and get the details

Thanks in advance
SSijo