如何获得定义为数组的每个初始条件的图？

Question

我是这个论坛的新手，

我有下一个代码，我需要的是能够从数组中提取每个元素并将其绘制出来，但是我对如何做到这一点感到困惑。 我了解部分原因是我只得到数组的末尾，因为for循环当然会返回该最终值。

代码

from numpy import linspace, zeros, asarray
import matplotlib.pyplot as plt
import numpy as np

def ode_EULER(f, C_i, dt, T):
    N_t = int(round(float(T)/dt)) #calculate number of iterations n+1
    f_ = lambda x, t: asarray(f(x, t)) #ensure that the list of equations are transform into array
    x = zeros((N_t+1, len(C_i))) #init array full with zeros [0. 0.]
    t = linspace(0, N_t*dt, len(x)) #start from 0 to 100  with len(x) number of samples
    x[0] = C_i #pass the inital conditions to the first array element
    for n in range(N_t): #start computations
        x[n+1] = x[n] + dt*f_(x[n], t[n])
    return x, t
          ## solve ODe
          # # z = odeint(model,z0,t)

def insystem():            #the system to be solved  
    def f(x, x2):          
        X1, X2 = x         #define both equations in one X (as vector)
        return [X2, X1-X2+2*((0.5)*((X2-X1)-(X2)-np.sign(X1-2)))] #[X2, X1-X2+2*(u)]
    #parameters 
    dt = 0.01 #precision
    T = 20 # Simulation time
    C_i = np.array([[0, 0],[1, 1],[2, 2],[3, 3]])

    nooics=len(C_i)
    for i in range(0,nooics):
     x_old, t_old = ode_EULER(f, C_i[i], dt, T)
    X1_old = x_old[:,0]
    X2_old = x_old[:,1]

    plt.plot(t_old, X1_old, 'b-',\
    t_old, X2_old, 'r-')
    plt.xlabel('time');
    plt.ylabel('S (blue), I (red)')
    plt.show()

if __name__ == '__main__':
    insystem()