On Wed, Sep 17, 2008 at 8:02 AM, Jason Merrill <[EMAIL PROTECTED]> wrote: > > On Sep 17, 2:20 am, Jason Merrill <[EMAIL PROTECTED]> wrote: >> Here's a monkeypatch that makes this work(ish) >> >> from sage.calculus.calculus import SymbolicExpression >> class FormalSymbolicExpression(SymbolicExpression): >> def __init__(self,expr): >> self.expr = expr >> # just delegate everything to the input expression >> for m in dir(expr): >> self.m = m >> def _repr_(self,simplify=False): >> return self.expr._repr_(simplify=False) >> # implement a _latex_ method >> >> SymbolicExpression.formal = lambda self: >> FormalSymbolicExpression(self) >> >> def formal(expr): >> try: >> return expr.formal() >> except AttributeError: >> return expr > > Right... so that delegation bit doesn't actually do anything. This > was leading to > > sage: simplify(formal(exp(I*pi))) > e^(pi*I) > > and presumably horrendous amounts of other strangeness. Here's > another try. It doesn't actually inherit from SymbolicExpression > anymore, which will probably cause some difficulty with isinstance > calls, but it's maybe a little closer > > from sage.calculus.calculus import SymbolicExpression > class FormalSymbolicExpression(): > def __init__(self,expr): > self.expr = expr > > def __getattr__(self,attrib): > return getattr(self.expr,attrib) > > def __repr__(self,simplify=False): > return self.expr._repr_(simplify=False) > > SymbolicExpression.formal = \ > lambda self: FormalSymbolicExpression(self) > > def formal(expr): > try: > return expr.formal() > except AttributeError: > return expr > > And now > > sage: simplify(formal(exp(I*pi))) > -1
Jason, Just a heads up -- your code above is going to become pointless when we switch to using Ginac as a backend for symbolic manipulation, since Sage will no longer keep its own expression tree. William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com 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://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
