1 | initial version |
The answer to your second question (substituting for $C$) is
soln[0].substitute({SR.var('_C'): 0})
This is because constants that appear in solutions of ODEs, like _C
(which is displayed as $C$), are not put in the global namespace, hence they have to be recovered from their names in the Symbolic Ring (SR) by SR.var('_C')
.