The existing bridge to/from Pynac has to include the forget() call, of course, and your example only shows that it works.
https://github.com/sagemath/sage/blob/master/src/sage/symbolic/expression.pyx#L1916 https://github.com/sagemath/sage/blob/master/src/sage/symbolic/expression.pyx#L1994 https://github.com/sagemath/sage/blob/master/src/sage/symbolic/assumptions.py#L559 https://github.com/pynac/pynac/blob/master/ginac/assume.cpp#L43 On Tue, Jun 20, 2017, 16:04 Stan Schymanski <schym...@gmail.com> wrote: > Actually, ex.is_real() queries the assumptions() data base, not the > GiNaC/Pynac info flags. Example: > var('test', domain='real') > print test.is_real() > forget() > print test.is_real() > > Returns: > True > False > > I think your proposal below would be great. Remove assume() from variable > creation, but get the information from Pynac and convert to assumptions > when calling maxima. > > > > > On 06/15/2017 08:17 AM, Ralf Stephan wrote: > > The "more persistent domains() database" exists already in part as > GiNaC/Pynac info flags that are set in parallel to Maxima's assumptions. > They can be queried with ex.is_real() etc...What is not saved in Pynac are > less elementary assumptions like x>1, y+z==pi. Now instead of caching all > assumptions in a database (either Python or C++) and sending to Maxima on > demand in bulk, another possibility could be, as you say, to just remove > the assume calls on variable creation because they are all elementary > assumptions. Then when Maxima needs them for integration, solving etc take > the information from Pynac and do assumes for just those variables that are > needed. Am I missing something? > > On Wednesday, June 14, 2017 at 6:14:39 PM UTC+2, Stan wrote: >> >> As mentioned in https://trac.sagemath.org/ticket/23138, the assume() >> command takes a lot of time, which is very annoying when defining a lot of >> variables using var() including a domain information. var('x', >> domain='real') passes the domain information to ginac and adds it as an >> assumption to assumptions(), so that it can be considered by maxima. >> However, since assumptions() can both store much more information than just >> the domain information, and on the other hand all the information is lost >> when someone executes forget(), I am wondering if this code should not be >> removed from src/sage/symbolic/ring.pyx, Lines 1017-1027, in favour of a >> more persistent domains() database, which could be injected into >> assumptions() by the user if needed. Any thoughts on this? >> >> Cheers >> Stan >> > -- > You received this message because you are subscribed to a topic in the > Google Groups "sage-devel" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/sage-devel/-A8ZzSKvYsA/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at https://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > > > -- > ________________________________________ > > Stan Schymanski > Riedstrasse 60 > 8604 Volketswil > Schweiz > > Ph: +41 (0)43 5420487 > _________________________________________ > > -- > You received this message because you are subscribed to a topic in the > Google Groups "sage-devel" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/sage-devel/-A8ZzSKvYsA/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at https://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
