Thank you very much, that did the trick. Uwe
Am Donnerstag, 17. September 2015 00:07:14 UTC+2 schrieb Aaron Meurer: > > If you don't tell solve() that beta_2 is a parameter, it assumes that > it is a constant. It then returns no solutions because it solves eq1 > and eq2 each for phi_2 and sees that they look different, because they > are only equal for certain values of beta_2 (at least, I'm fairly sure > this is what is happening). > > You can get the solutions by telling solve that beta_2 is a parameter > > In [14]: solve([eq1, eq2], [phi_2, beta_2]) > Out[14]: [(0.0, 1.0), (1.0, 0.0)] > > Aaron Meurer > > On Wed, Sep 16, 2015 at 6:12 AM, Uwe Fechner <[email protected] > <javascript:>> wrote: > > Hello, > > > > I try to calculate the tangent of a circle. This is a quite simple > system of > > equations (one is quadratic), > > but sympy fails (empty solution set). Any idea why? > > > > from __future__ import division > > from sympy import * > > from sympy.solvers import solve > > > > init_printing(use_latex = True) > > r, phi_0, phi_1, phi_2, beta_0, beta_1, beta_2= symbols('r phi_0, phi_1, > > phi_2, \ > > beta_0, beta_1, beta_2') > > > > if True: > > if True: > > phi_0 = 0 > > beta_0 = 0 > > phi_1 = 1. > > beta_1 = 1. > > r=1. > > eq1 = Eq((phi_2 - phi_1) * (phi_2 - phi_1) + (beta_2 - beta_1) * > (beta_2 > > - beta_1) - r*r) > > eq2 = Eq((phi_2 - phi_0) * (phi_2 - phi_1) + (beta_2 - beta_0) * > (beta_2 > > - beta_1)) > > result = solve([eq1, eq2], phi_2) > > print result > > > > The result is an empty list. Any idea, how to fix this? > > Expected result: phi_2 = 1. > > > > Any hints appreciated! > > > > U. Fechner, TU Delft > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "sympy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to [email protected] <javascript:>. > > To post to this group, send email to [email protected] > <javascript:>. > > Visit this group at http://groups.google.com/group/sympy. > > To view this discussion on the web visit > > > https://groups.google.com/d/msgid/sympy/09115c90-e2b9-40e4-93e1-42e9696adc22%40googlegroups.com. > > > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/156da035-589b-4248-9780-9188f34c3aee%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
