>>>>> "Stefan" == Stefan Kuzminski <pon...@ya...> writes: Stefan> Hi, When I try to use Psyco with matplotlib-0.71 I get the Stefan> error below. Stefan> http://psyco.sourceforge.net/ Stefan> self.figwidth*self.dpi, TypeError: unsupported operand Stefan> type(s) for *: 'BinOp' and 'BinOp' Stefan> Any ideas? thanks, Stefan I don't have much experience with pysco. All I can add is that BinOp is an extension code class that derives from LazyValue, and is designed to defer evaluation of scalars and operations until needed. The point of this is to allow you to do things like window resizes and have all your transforms update w/o needing an observer pattern. The classes are described in a bit more detail in http://matplotlib.sf.net/matplotlib.transforms.html . Does pyscho play well with extension modules in general? Surely it must. It's possible that this is revealing an error in mpl code, pycxx code, or it may be on the psyco side. I would be willing to work with you to compose a minimal example if you want to pursue it. You could start with from matplotlib.transforms import Value v1 = Value(1) v2 = Value(2) v3 = v1*v2 v1.set(2) print v3.get() # should be 4 JDH