On Tue, Nov 06, 2007 at 10:41:17AM -0300, Eduardo Rodrigues wrote:
Hi, I am starting in Python. I usually use Maple and I am with a problem to do the same project in Python. I would like to solve an equation like x+y+1=0 for x. In Maple I use "solve(x+y+1=0,x);". Do exist a similar command in Python/NumPy/SciPy?
Do you want a numericaly result, given the value of y, or do you want a formal result ? The numerical value can be calculated using scipy, for linear equation with the method exposed by Michael Nandris, for non linear equations, you should look at scipy.optimize.zeros. If you want a formal result, or a functional result, you can use sympy: from sympy import solve, Symbol x = Symbol('x') y = Symbol('y') f = solve(x+y+1, x) # f gives you the symbolic result F = lambda v: f.subs(y, v) F is a function that returns the exact expression of the root of you equation. If you have several roots, than you need to do something like: F = lambda v: [r.subs(y, v) for r in f] Currently sympy is still yound, and won't be able to solve everythin you throw at it. HTH, Gaël