The following example comes from the in-source documentation for ode_solver:
sage: T = ode_solver()
sage: g_1= lambda t,y: [y[1]*y[2],-y[0]*y[2],-0.51*y[0]*y[1]]
sage: T.function=g_1
sage: T.y_0=[0,1,1]
sage: T.scale_abs=[1e-4,1e-4,1e-5]
sage: T.error_rel=1e-4
sage: T.ode_solve(t_span=[0,12],num_points=100)
sage: f = T.interpolate_solution()
sage: f(pi) # slightly random precision
0.53794725135406318
It should be possible to set these attributes using arguments to the constructor, but this fails:
sage: T = ode_solver(g_1,y_0=[0,1,1],scale_abs=[1e-4,1e-4,1e-5],error_rel=1e-4)
sage: T.ode_solve(t_span=[0,12],num_points=100)
sage: f = T.interpolate_solution()
sage: f(pi)
Traceback (click to the left for traceback)
...
TypeError: object of type 'NoneType' has no len()
