If you do not install one or more optional modules you will still be able to use PyPedal, although some features may not be available to you. Details on installing the extensions listed above can be found on their respective websites. All of these extensions are available for Unix-type operating systems (e.g. Linux, Mac OS X) as well as for Microsoft Windows; most sites also provide binary installers for Windows. Python extensions can usually be installed by unzipping/untaring the archives, entering the folder, and issuing the command "python setup.py install" as a root/administrative user. Note that NetworkX and ReportLab are not installed by the Enthought Python Distribution for Windows. I have found that installations from source on Linux are sometimes tricky, but I have found that Sage (http://www.sagemath.org/index.html) does a great job of getting clean builds of the trickier pieces, such as Numpy and matplotlib.
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