def _gravity_f_j_jtimes(g):
def f(t, y, fout):<EOL><INDENT>x, v = y<EOL>fout[<NUM_LIT:0>] = v<EOL>fout[<NUM_LIT:1>] = -g<EOL><DEDENT>def jac(t, y, jmat_out, dfdx_out=None, fy=None):<EOL><INDENT>jmat_out[<NUM_LIT:0>, <NUM_LIT:0>] = <NUM_LIT:0><EOL>jmat_out[<NUM_LIT:0>, <NUM_LIT:1>] = <NUM_LIT:1><EOL>jmat_out[<NUM_LIT:1>, <NUM_LIT:0>] = <NUM_LIT:0><EOL>jmat_out[<NUM_LIT:0>, <NUM_LIT:1>] = <NUM_LIT:0><EOL><DEDENT>def jtimes(v, Jv, t, y, fy, user_data=None, tmp=None):<EOL><INDENT>Jv[<NUM_LIT:0>] = v[<NUM_LIT:1>]<EOL>Jv[<NUM_LIT:1>] = <NUM_LIT:0><EOL><DEDENT>return f, jac, jtimes<EOL>
RHS, jacobian, and jacobian-vector product for
        particle falling under influence of gravity