[GiNaC-devel] Positive add and mul, LaTeX printing

Dear All, I think it would be nice if GiNaC will learn that a sum or product of two positive expressions is again a positive expression. This will help, for example, to simply formulae like ((1+x)^{1/2})^2, where x is a positive symbol. It would be also a better LaTeX printing of complicated formulae if \mathrm will be used instead of \mbox (the later is not scaled in fractions, for example). I am attaching a patch which makes these two things. Best wishes, Vladimir -- Vladimir V. Kisil email: kisilv@maths.leeds.ac.uk -- www: http://maths.leeds.ac.uk/~kisilv/