Hi everyone, Last week we briefly talked about removing the generated post-Cython .c and .cpp files from the repository. They have become something of a burden to maintain, and the diffs simply get too large. I've taken a stab at removing these, which I've placed in a bundle here: http://yt.enzotools.org/files/cython-changes.hg The changeset in question is bce1c775bb84 . This starts by removing .c and .cpp files generated by Cython and adding the appropriate information about how to generate the .c and .cpp files to the setup.py files for RAMSES and the amr_utils directories. Additionally, dependencies are included in these setup.py files. However, to get Cython to play nicely with NumPy, I've had to add in a routine that I found written by Matthew Brett. I updated it to include some C++ support. Additionally, as a safeguard for those systems were Cython is not already included, I have added a brief routine that checks whether or not Cython is installed. If it is not, it attempts to install it. This will still fail on systems where superuser privs are required, but that should not be the case in the majority of yt installations that are not on OSX. On OSX this will require sudo-ing the installation. I'd really appreciate if at least one or two people could unbundle this and test out that "python2.6 setup.py build_ext -i" works, and it would be *extra* helpful if you could try this on a machine where Cython isn't installed, and check that the auto-installation of Cython actually works. I've tested it a couple places and it works, but I hope that others can test it as well. Anyway, thanks for reading this far, and if you get a chance to test that would be amazing. And if you do, please refrain from pushing these changes until we get settled on how well they work. Hopefully by making amr_utils.c a bit lighterweight we can be more free to make changes to the Cython routines and people can get them faster. Best, Matt