import numpy as np
import matplotlib.pyplot as plt

plt.style.use('ggplot')
#plt.figure(figsize=(20,10))

N=500 # number of steps
T=10   # simulation time in seconds

c = 1
l = 1

t = np.empty(N)
V = np.empty(N)
I = np.empty(N)

dt=T/N;

# initial values
V[0]=1
I[0]=0

for k in range(0,N-1):
	I[k+1]=I[k]+(1/l)*V[k]*dt	
	V[k+1]=V[k]-(1/c)*I[k+1]*dt
	t[k+1]=t[k]+dt
	

plt.plot(t,V,label='Capacitor Voltage')
plt.plot(t,I,label='Capacitor Current')


plt.xlabel('Time (s)')
plt.title('Undriven LC circuit')
plt.legend()
plt.show()