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Re: Simplifying Derivatives
Kenneth S. Crumpton wrote: > > I am computing symbolically derivatives of orbit equations. The answers > are coming out correctly but how do I keep it from substituting what > various symbols are equal to ? (E.g., r = sqrt(x^2+y^2+z^2); I just > want to see r in the answer and not the expansion) Thanks. > > Steve Crumpton > Systems Engineer, Raytheon You will need to use a transformation rule such as expr/.x^2+y^2+z^2->r^2. The use of transformational programming is one of the three programming paradigms in mathematica. If you are going to do anything very complicated(In general, algebraic simplification is complicated), I would recommend a third party book like David Wagners Power Programming book to help you out.