Then use simplistic rules of derivative like d(x+c) = dx, d(ax+c) = a dx. Sent from Mail for Windows 10 From: JS S Your suggestion is true. However, using ``Derivative(f(x), x) * 1/Derivative(x+1, x)`` explicitly every time is not very systematic approach. If we know "Hey, df(x)/d(x+1) equals (df(x)/dx)/(d(x+1)/dx)!", then why don't we let SymPy know to automatically deal with this case with same approach? Let me put this in another word. We know that ``dsin(x)/dx == cos(x)``. Then, how can we use this to evaluate ``expr = 1+Derivative(sin(x), x)``? Although we can evaluate this by manually substituting like ``expr.subs(Derivative(sin(x), x), cos(x))``, we let SymPy know that ``dsin(x)/dx == cos(x)``, so that we can just use ``expr.doit()``. My idea is same: ``f(x).diff(x+1)`` is better than ``(Derivative(f(x), x) * 1/Derivative(x+1, x)).doit()``. If we can do something explicitly, then it would be better to do it implicitly.
-- -- |
- [sympy] Suggestion on Derivative and Expr._diff_wrt Francesco Bonazzi
- RE: Re: [sympy] Suggestion on Derivative and Expr._diff_... Vishesh Mangla
- RE: Re: Re: [sympy] Suggestion on Derivative and Expr._d... Vishesh Mangla
- Re: Re: [sympy] Suggestion on Derivative and Expr._diff_... mcpl snu
