The best technique is to strip down the problem to the smallest part that produces the error.
In your case, you include this expression: Eq((r1-r3)((1-cos(theta-phi)* ddotphi-sin(theta-phi)*dotphi**2)-2*(r1-r2)*ddottheta,g*sin(theta))) The (r1-r3) produces an Add object, and the parentheses that follow try to call that Add object with the value inside the parentheses... Maybe you meant to multiply like this? Eq((r1-r3) * (1-cos(theta-phi)* ddotphi-sin(theta-phi)*dotphi**2)-2*(r1-r2)*ddottheta,g*sin(theta)) -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAH6Pt5qOT8zD6yr5_Oat9dA4pEmqvurVbT260kR%3D%3D80QOnvEEg%40mail.gmail.com.
