The first approach was hackish (actually both are, but the decorator way is *significantly* better). And I agree, I'm still not sure this a problem worth solving. Just food for conversation. I posted some timings on the decorator PR https://github.com/sympy/sympy/pull/8297
The core tests ran about 6% slower on my machine, but the long running ones ran only neglibly slower. The overhead of calling `_ask` without a timeout set is only ~70 ns on my machine. With one set it's more intrusive, due to the need to lookup the time. Polling is *not* the nicest approach to this, I fully agree. On Thursday, October 23, 2014 1:23:07 PM UTC-5, James Crist wrote: > > For the large expressions that we see in `mechanics`, calls to `simplify` > can take an extremely long time. However, for simple expressions, > simplification is desirable. Currently we don't simplify by default inside > any of our library code, as it's impossible to tell whether the expression > can be reasonably simplified or not. If a `timeout` argument was added to > such functions though, one could simply run > > >>> simplify(expr, timeout=some_reasonable_max_time) > > and get the best of both worlds. > > However, this isn't the easiest thing to do in Python. The best > *composable* option is to use signal.alarm, which is only available on *NIX > systems. This can also cause problems with threaded applications. Checks > for windows or not running in the main thread could be added to handle this > though, but would limit it's use. > > --- > > A second option would be to implement a "pseudo-timeout". This only works > for functions that have many calls, but each call is guaranteed to complete > in a reasonable amount of time (recursive, simple rules, e.g. `fu`). The > timeout won't be exact, but should limit excessively long recursive > functions to approximately the timeout. I wrote up a quick implementation > of this here <https://gist.github.com/jcrist/c451f3bdd6d038521a12>. It > requires some function boilerplate for each recursive call that *can't* be > replaced with a decorator. However, it's only a few lines per function. I > think this is the best option if we were to go about adding this. > > Thoughts > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/4e02bf63-6b16-4922-ad27-75074429185f%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
