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我正在使用python ODE來求解Van der Pol方程。我想要做的是找到一次調用積分（t）方法期間調用ODE的派生數量的次數。我使用的解算器是isoda。我試圖找到在沒有jacbian函數的情況下在一次調用期間調用衍生物的次數，以及包含jacobian函數時調用jacobian函數的次數。lsoda.error：處理參數列表中的回調jac失敗
def modified_vanderpol_integrator_demo(dt_min=1e-3, dt_max=10., mu=100.):
# define a class to store the number of calls
class F:
def __init__(self):
self.callsydot = 0
self.callsjac = 0
def ydot(self,t, y, mu):
self.callsydot += 1
x, v = y[0], y[1]
return array([v, mu*(1- x*x)*v - x])
def jac(self, t, y, mu):
self.callsjac += 1
return array([[0, 1], [2*mu*v*x - 1, mu*(1-x*x)]])
Dt = linspace(dt_min, dt_max, 1000)
Num_of_times1 = []
Num_of_times2 = []
for dt in Dt:
xinitial = array([1.0, 2.0]) # initial value
f1 = F()
r1 = ode(f1.ydot)
r1.set_integrator('lsoda')
r1.set_initial_value(xinitial)
r1.set_f_params(mu)
r1.integrate(dt)
Num_of_times1.append(f1.callsydot)
f2 = F()
r2 = ode(f2.ydot, f2.jac)
r2.set_integrator('lsoda', with_jacobian=True)
r2.set_initial_value(xinitial)
r2.set_f_params(mu)
r2.integrate(dt)
Num_of_times2.append(f2.callsjac)
plt.plot(Dt, Num_of_times1)
plt.plot(Dt, Num_of_times2)
plt.show()
當我運行該腳本，我得到的消息
create_cb_arglist: Failed to build argument list (siz) with enough arguments (tot-opt) required by user-supplied function (siz,tot,opt=2,3,0).
Traceback (most recent call last):
File "stiffequations.py", line 118, in <module>
modified_vanderpol_integrator_demo(dt_min=1e-3, dt_max=10., mu=100.)
File "stiffequations.py", line 111, in modified_vanderpol_integrator_demo
r2.integrate(dt)
File "/usr/local/lib/python2.7/dist-packages/scipy/integrate/_ode.py", line 394, in integrate
self.f_params, self.jac_params)
File "/usr/local/lib/python2.7/dist-packages/scipy/integrate/_ode.py", line 1193, in run
y1, t, istate = self.runner(*args)
lsoda.error: failed in processing argument list for call-back jac.
爲什麼出現這種情況，如何解決？ 謝謝。