08-01.py
Programme Python de l'Interros des Lycées 1re M
X = [-5,-3,0,1,2,10]
P = [0.2,0.3,0.05,0.05,0.3,0.1]
def esperance(X,P):
e = 0
for i in range(len(X)):
e += X[i]*P[i]
return e
def variance(X,P):
v = 0
e = esperance(X,P)
for i in range(len(X)):
v += P[i]*(X[i]-e)**2
return v
def ecartype(X,P):
return variance(X,P)**0.5
print("L'espérance est :",esperance(X,P))
print("La variance est :",variance(X,P))
print("L'écart-type est :",ecartype(X,P))
Y = []
for i in X:
Y.append(i*i)
V = esperance(Y,P) - esperance(X,P)**2
print(V)