Re: Error in Mathematica?

*To*: mathgroup at yoda.physics.unc.edu*Subject*: Re: Error in Mathematica?*From*: Ronald D. Notestine <ronald at sccs.chukyo-u.ac.jp>*Date*: Tue, 09 Nov 93 02:07:19 +0900

This is one of those that Nancy Blachman poses often in her talks. When you input x=b then x^2/.x->a, first MMA evals the x^2 to b^2, then it evals the x->a to b->a, then it applied the rule to get a^2. When you enter x=2 then x^2/.x->7, MMA first evals the x^2 to 2^2 to 4, then it applies the rule x->7. Of course, now there is no x remaining on the left of the slash-dot. Nancy Blachman's book, "Mathematica a Prectical Approach" has a number of examples of this sort of thing (at least, if I recall correctly, it does.) Ronald D. Notestine Faculty of Management Chukyo University Nagoya, Japan ronald at sccs.chukyo-u.ac.jp fax: 81-52-835-7196