Yes, don't use a SAT solver. It requires all metadata from all packages (~30MB uncompressed) and gives hard to predict results in some cases. Also the lack of fixed dependencies is a substantial problem for a SAT solver. Overall, we think it makes more sense to use a simple backtracking dependency resolution algorithm.
Sebastien Awwad (CCed) has been looking at a bunch of data around the speed and other tradeoffs of the different algos. Sebastien: Sometime next week, can you write it up in a way that is suitable for sharing? Justin On Fri, Feb 10, 2017 at 1:59 PM, Wes Turner <[email protected]> wrote: > From the discussion on https://github.com/pypa/pip/ > issues/988#issuecomment-279033079: > > > - https://github.com/ContinuumIO/pycosat (picosat) > - https://github.com/ContinuumIO/pycosat/blob/master/pycosat.c (C) > - https://github.com/ContinuumIO/pycosat/blob/master/picosat.c > - https://github.com/ContinuumIO/pycosat/tree/master/examples > - https://github.com/enthought/sat-solver (MiniSat) > - https://github.com/enthought/sat-solver/tree/master/ > simplesat/tests > - https://github.com/enthought/sat-solver/blob/master/ > requirements.txt (PyYAML, enum34) > > > Is there a better way than SAT? > > On Fri, Feb 10, 2017 at 12:20 PM, Pradyun Gedam <[email protected]> > wrote: > >> Yay! Thank you so much for a prompt and positive response! I'm pretty >> excited and looking forward to this. >> >> On Thu, Feb 9, 2017, 20:23 Donald Stufft <[email protected]> wrote: >> >> I’ve never done it before, but I’m happy to provide mentoring on this. >> >> On Feb 8, 2017, at 9:15 PM, Pradyun Gedam <[email protected]> wrote: >> >> Hello Everyone! >> >> Ralf Gommers suggested that I put this proposal here on this list, for >> feedback and for seeing if anyone would be willing to mentor me. So, here >> it is. >> >> ----- >> >> My name is Pradyun Gedam. I'm currently a first year student VIT >> University in India. >> >> I would like to apply for GSoC 2017 under PSF. >> >> I currently have a project in mind - the "pip needs a dependency >> resolver" issue [1]. I would like to take on this specific project but am >> willing to do some other project as well. >> >> For some background, around mid 2016, I started contributing to pip. The >> first issue I tackled was #59 [2] - a request for upgrade command and an >> upgrade-all command that has been open for over 5.5 years. Over the months >> following that, I've have had the opportunity to work with and understand >> multiple parts of pip's codebase while working on this issue and a few >> others. This search on GitHub issues [3] also provides a good summary of >> what work I've done on pip. >> >> [2]: https://github.com/pypa/pip/issues/988 >> [2]: https://github.com/pypa/pip/issues/59 >> [3]: https://github.com/pypa/pip/issues?q=author%3Apradyunsg >> >> Eagerly-waiting-for-a-response-ly, >> Pradyun Gedam >> >> _______________________________________________ >> Distutils-SIG maillist - [email protected] >> https://mail.python.org/mailman/listinfo/distutils-sig >> >> >> >> — >> >> Donald Stufft >> >> >> _______________________________________________ >> Distutils-SIG maillist - [email protected] >> https://mail.python.org/mailman/listinfo/distutils-sig >> >> > > _______________________________________________ > Distutils-SIG maillist - [email protected] > https://mail.python.org/mailman/listinfo/distutils-sig > >
_______________________________________________ Distutils-SIG maillist - [email protected] https://mail.python.org/mailman/listinfo/distutils-sig
