On 12/6/06, Robert Bradshaw <[EMAIL PROTECTED]> wrote: > > First, let me say that I like this proposal. > > On Dec 6, 2006, at 5:03 PM, William Stein wrote: > > > Sage calculus > > f = alg expr > > > > f.subs(var, val, ...) > > f.subs(dict) > > f.subs(list of pairs) > > implement recursively, with base case functions of 1 var and vars and > > constants being clear. > > I would vote for f.subs(var=val, ...) as well. > > > f.function(*args) - returns a callable version of f, which otherwise > > works in same way. Output is result of subs. > > this just another formal function, but with a call method. > > Also, function((vars...),expr) makes an evaluatable function. > > The motivation for not providing a call function to begin with is > that the arguments have not been specified yet? I still think f(x,y) > = sin(x)*cos(x+y+3) is the most "natural" syntax, but alas it > requires the preprocessor. > > > f.derivative(var) - we completely implement. > > Even if we implement this (which should be relatively easy), should > we pass the results to maxima to try and simplify it? On that note, > should we have a f.simplify(), etc. method?
We should definitely have a way of simplifying an algebraic expression. Also, we should be able to expand a simplified expression. And we also will want to have a method that tries to isolate a variable. These should all be doable via Maxima. > > f.integral(var, optional endpoints) - feed expr to maxima (or maple or > > mathematica or mathomatic or yaccas or??) and let it compute integral > > symbolically. Sage_eval the result (if possible - if that fails, > > maybe wrap the external object formally). > > > > Basic functions: all functions like sin, cos, exp, special funcs, > > etc, will be defined as formal functions - a lot of this is already > > done. > > -- Bobby Moretti [EMAIL PROTECTED] --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
