a ¬>> from sympy import euler_equations, Symbol, Function >>> x = Function('x') >>> t = Symbol('t') >>> L = (x(t).diff(t))**2/2 - x(t)**2/2 >>> euler_equations(L, x(t), t) [Eq(-x(t) - Derivative(x(t), (t, 2)), 0)] >>> u = Function('u') >>> x = Symbol('x') >>> L = (u(t, x).diff(t))**2/2 - (u(t, x).diff(x))**2/2 >>> euler_equations(L, u(t, x), [t, x]) [Eq(-Derivative(u(t, x), (t, 2)) + Derivative(u(t, x), (x, 2)), 0)] References ========== .. [1] https://en.wikipedia.org/wiki/Euler%E2%80%93Lagrange_equation zFunction expected, got: %srcss|]}t|ƒVqdS©Nr )Ú.0Úvarr r úd/Users/vegardjervell/Documents/master/model/venv/lib/python3.9/site-packages/sympy/calculus/euler.pyÚ Vóz"euler_equations..css|]}t|tƒVqdSr )Ú isinstancer)rÚvr r rrXrz!Variables are not symbols, got %sz"Variables %s do not match args: %scs g|]}|jˆvrt|jƒ‘qSr )ÚexprÚlenÚ variables)rÚd©Úfuncsr rÚ _s ÿz#euler_equations..é)r ÚtupleZatomsrrÚ TypeErrorÚargsÚallÚ ValueErrorÚmaxrrÚrangerrZ NegativeOnerÚappend) ÚLrÚvarsÚfÚorderZeqnsÚeqÚiÚpZnew_eqr rrÚeuler_equationss8:    ÿ 4   r,N)r r )Ú__doc__Ú itertoolsrZsympy.core.functionrrrZsympy.core.relationalrZsympy.core.singletonrZsympy.core.symbolrZsympy.core.sympifyr Zsympy.utilities.iterablesr r,r r r rÚs