Plot variables are identified by a sequence number in OYSTER, and are defined in terms of OYSTER data variables in set_plotdata (and the corresponding function set_ploterr. The corresponding plot variable name is defined in the set_axitems function, which should have exactly the same ordering. The following additional information needs to be entered for each plot variable.
Each plot variable's ID is entered in set_plotlabels for the index label it requires so that it is displayed together with the name in the plots. In set_plotloops, the loop count is set to one for those indices which do not occur in the plot variable. These functions and procedures are all found in plot.pro. Finally, the plot variable's ID need to be entered in ww_setxaxis, ww_setyaxis, and set_zaxis if it's selection requires and additional index selection by the user.