Hi, Le lundi 30 mai 2016 17:31:14 UTC+2, Zach Elgood a écrit : > > Hello again, > Thank you very much for the previous help. Some of the research I do > involves using actions to calculate things like the Euler Lagrange > equations. I was wondering if this is possible to do in Sage. >
To my knowledge, no variational calculus is implemented in Sage yet. But this would be a nice project! > For example, if I had the Lagrangian > > Nabla_mu(phi) Nabla^mu (phi)-m^2*phi^2 > > how would I go about constructing one? I tried simply defining it, but I > keep getting the attribute 'sage.symbolic.expression.Expression' object > has no attribute '_domain' when I try and take the covariant derivative > of it. > A reason could be that phi has not been defined as a scalar field (i.e. as phi = M.scalar_field(...)), but merely as a symbolic expression. Is it the case? Best wishes, Eric. -- You received this message because you are subscribed to the Google Groups "sage-support" 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 https://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
