python 将dataframe的某一列离散数据转换为数值数据

from sklearn import preprocessing

def bianma(a, name):
    type = a.ix[:, name]
    a[name].fillna('0', inplace=True)
    le = preprocessing.LabelEncoder()
    le.fit(type)
    a[name] = (le.transform(type.astype(str))).T

  bianma(train, '待转换的数据列名')