http://www.python-simple.com/python-pandas/dataframes-indexation.php
# -*- coding: utf-8 -*-
import pandas as pd
df = pd.read_excel('donnees_lancer.xlsx')
df.head()
len(df)
df.columns
df.describe()
df2 = pd.read_excel('ensemble.xlsx',header=7,sheetname=0)
df2.head(10)
df2.describe()