3.1 Polynomials

As an example, a polynomial in the variables ['x','y','z'] can be represented by a string of the form

p = 'df((x^3+y)^2, x, y, 2)  + ((1+x)+y*z*y)*(z^3-9)'
In this expression df is the first derivative with respect to x and the second one with respect to y.