Log(-1) is immediately replaced by %i*%pi.
There is then only one log in the expression.
Perhaps you can use subst(log(1-a)-%i*%pi,log(a-1), expression..).
Assume(a<1) probably has no affect on log simplification.
RJF
> -----Original Message-----
> From: maxima-bounces at math.utexas.edu [mailto:maxima-
> bounces at math.utexas.edu] On Behalf Of Hugemann
> Sent: Sunday, November 12, 2006 5:41 AM
> To: maxima at math.utexas.edu
> Subject: logcontract
>
> I have a problem manipulating a certain term. This problem can be
> reduced to the following basic problem:
>
> assume(a<1);
> log(a-1)-log(-1);
> logcontract(%);
>
> I would expect this to give the desired result log(1-a), but it doesn't.
> It just doesn't do anything. Any ideas or explanations?
>
> Greetings from M?nster, Germany
> Wolfgang Hugemann
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