The function in question is sort-of available as sage.functions.other.symbolic_limit (which is an inert form, so it requires a further "simplify").
On Thursday 3 October 2024 at 08:29:50 UTC-7 Nils Bruin wrote: > On Thursday 3 October 2024 at 04:44:12 UTC-7 Emmanuel Charpentier wrote: > > sage: F.limit(X[0]=3) Cell In[9], line 1 F.limit(X[Integer(0)]=Integer(3)) > ^ SyntaxError: expression cannot contain assignment, perhaps you meant > "=="? > > Indeed, the current limit function and method get their arguments > (variable and value) by analysing a single named argument, whose name must > be a literal. From limit?? : > > The restriction here is python's processing of optional arguments. These > must have simple names. You can already use > """ > limit(x0,**{str(X[0]):1}) > """ > now, which isn't beautiful but at least it establishes the function. > Allowing an explicit dictionary argument would likely open up a whole slew > of other issues. It looks to me like we're missing a very simple form for > limit that should be the primitive to all of this: > limit( f, x, 1) > i.e.: expression to take limit of, variable with respect to take limit, > limit value. Then one could just write limit( F, X[0], 0) and one would get > the default processing of arguments for python for free. We wouldn't rely > on the programmatic pun of using python identifiers to stand in for our > symbolic variables. > Further convenience routines that use syntactic sugar to make things > resemble more mathematical notation can then be built on top, but at least > the general primitive is available underneath. > It may be hard to figure out a way to make such a routine available under > an easily found name while remaining compatible with what exists now. > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/71fc67b2-2ff3-48d6-838f-9400a74a6738n%40googlegroups.com.