Dear All, I propose to add the evaluation rule log(p^a) -> a*log(p) if p>0 and a is real. The patch (including the respective check) is attached. Best wishes, Vladimir -- Vladimir V. Kisil email: kisilv@maths.leeds.ac.uk www: http://www.maths.leeds.ac.uk/~kisilv/ Book: Geometry of Mobius Transformations http://www.worldscientific.com/worldscibooks/10.1142/p835