Vensim Analysis tools provide fast, flexible ways to find information about a model and its simulations. Custom output allows you more control over the appearance of graphs. The Graph tab of the Control Panel allows you to manage Custom Graphs. For most purposes you will probably want to work just with the graphs attached to the model and this can be done using the Custom Graph Editor described in this chapter. You can also customize the output of the Table tool and Bar Graph tool and create custom reports, though this can only be done with separate graph description files.
This chapter:
| • | Describes how to use the Custom Graph Editor. |
| • | Describes the Custom Table Editor. |
| • | Describes the structure of .vgd files. |
| • | Explains how to customize the Graph tool. |
| • | Explains how to customize the Bar Graph tool. |
| • | Explains how to customize the Table tool |
| • | Explains how to write custom reports |
Overview
Customized Graphs allow you to display more than one variable, with more than one scale, on a single graph. Customized Tables allows you to select the variables that will appear on a table. Customized Bar Graphs allow you to display values for multiple variables on a single bar graph. Reports allow you to compile a number of output values for display inside of text. You also have more control over labeling when using Customized tools.
There are two ways to create customized output. The first, and simplest, is to use the Custom Graph Editor or Customer Table Editor.. These are interactive dialogs that makes it very easy to set up a custom graph or table. These editors are fast and easy to use, but only works for custom graphs and tables. In addition, there are some Custom Graph options that cannot be accessed from it.
The other way to create customized output formats is to write a description of the output you want in a Vensim Graph Description (.vgd) file. A .vgd file is a text file containing keywords and values that describe what is to be displayed in a graph or table and specify how to label it. The Custom Graph Editor stores the graphs you create in .vgd format described in this chapter. By default this information is contained in the model file but is can also be saved as a .vgd file (see Chapter 11). You can move back and forth between editing the text file form and using the Custom Graph Editor. However, care must be taken not to modify a graph definition file directly and use the Custom Graph Editor at the same time.
