Build prerequisites for PyQwt-4.2.2.tar.gz:
The source package PyQwt-4.2.2.tar.gz contains the sources of the Qwt-4.2.0 library with a patch to force an update of the axis scales after zooming. You have the option to compile and link those sources statically into PyQwt (easiest for most users).
However, the configure.py script lets you build PyQwt against a shared or static Qwt-4.2.0 library (not the 4.2.0rcX release candidates because of API enhancements).
To exploit the full power of the QwtPlot widget, you should install at least one the Numerical Python extensions: NumPy, numarray, or Numeric.
I am using NumPy-1.0.1.tar.gz, numarray-1.5.2.tar.gz, and Numeric-24.2.tar.gz. NumPy is actively developed and recommended. numarray and Numeric are unmaintained.