from scipy import * 
import numpy as np
from scipy.integrate import odeint
from matplotlib import pyplot as plt


g,mu,m,alpha = 10,0.1,0.1,1.3
tau=m/mu
def deriv(v,t):
    return g-(mu/m)*v**alpha
   
t=linspace(0,5*tau,10000)
f=odeint(deriv,0,t)
plt.plot(t,f)
plt.show()


g,mu,m,l = 10,0.1,0.1,0.5
omega0=(g/l)**0.5
def derivsec(TH,t):
    theta=TH[0]
    thetap=TH[1]
    return [thetap,-omega0**2*sin(theta)-(mu/m)*thetap]
t=linspace(0,20*pi/omega0,10000)   #On definit l'intervalle de temps
g=odeint(derivsec,[pi/4,0],t)  #retourne une matrice deux colonnes avec x et xp aux differents instants

plt.plot(t,g[:,0])
plt.show()