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Voici mon programme :

from __future__ import division
from scipy import *
from pylab import *
from LF_Schechter import *

L_z = []
L_alpha = []
L_l_star = []
L_phi_star = []

f = open("Tableau des valeurs.csv",'r') #ouvre le tableau de valeur
f.readline() #saute une ligne

for ligne in f:
mots = ligne.split() #découpe les lignes en mots
z1 = float(mots[0]) #attribue les colonnes
l_star1 = float(mots[1])
a1 = float(mots[2])
phi_star1 = float(mots[3])
L_z = L_z + [z1] #ajute les valeurs aux listes
L_alpha = L_alpha + [a1]
L_l_star = L_l_star + [l_star1]
L_phi_star = L_phi_star + [phi_star1]

z = array(L_z)
a = array(L_alpha)
l_star = array(L_l_star)
phi_star = array(L_phi_star)

figure1 = figure()

l = arange(40.1,43.3,0.2)

for n in range(5):
phi = schechter(l,l_star[n],a[n],phi_star[n])
title(ur"$H_alpha $ $ LFs $ $ from $ $ z $ $ \backsim $ $ 0.16 $ $ to $ $ z $ $ \backsim $ $ 0.4$", fontsize=20)
xlabel(ur"$l$", fontsize=20)
ylabel(ur"$\phi(l) $ $ Mpc^{-3}$", fontsize=20)
yscale('log') #transforme y en echelle log
xlim(40.1,43.3)
ylim(1e-1,1e-7)
gca().invert_yaxis() #inverse l'axe des ordonnées
plot(l,phi,label=z[n])

legend(bbox_to_anchor=(0.02, 0.98), loc=2, borderaxespad=0.)

show()