PHASE PORTRAITS

Now I want to introduce you to a nice online tool which might help you plot some of these slope fields. (if you get tired of doing this by hand and your calculator can't plot these for you) It is called PPLANE (named for the term phase plane, of course). It is being developed by John C. Polking and some of his colleagues at Rice University. The software is really just a set of m-files that MatLab executes. MatLab is a Matrix Laboratory software package that is very popular with many mathematicians and engineers. Before you actually visit the site, you should remember that there are a few syntax notes that you need to understand. After all, this is a computing tool, much like a calculator, and it requires a certain syntax in order to function properly. You may want to keep this window open while you are using the tool so that you can read through the following notes as you plug along for the first time. Just minimize it and pull it up whenever you need it. The link to PPLANE is at the bottom of the page, but read (at least skim it, please) through the following before you click. As you may have guessed by now, the directions are essentially the same as those for the DFIELD tool.

Click Here in order to use PPLANE. Note: There is some introductory stuff at the top of the page. In order to crank up the tool, you must click on the grey button labelled PPLANE 2005.10

If you are interested in some of the more advanced options available with PPlane, please ask me--or just hunt around on your own and experiment with some things.

Last Updated: 08/22/07