machine learning in coding（python）：拼接原始数据；生成高次特征

拼接原始数据：

train_data = pd.read_csv('train.csv')
test_data = pd.read_csv('test.csv')
all_data = np.vstack((train_data.ix[:,1:-1], test_data.ix[:,1:-1]))

>>> a = np.ones((2,2))
>>> b = np.eye(2)
>>> print np.vstack((a,b))
[[ 1.  1.]
 [ 1.  1.]
 [ 1.  0.]
 [ 0.  1.]]
>>> print np.hstack((a,b))
[[ 1.  1.  1.  0.]
 [ 1.  1.  0.  1.]]

生成高（2）次特征：

def group_data(data, degree=2, hash=hash):
    new_data = []
    m,n = data.shape
    for indicies in combinations(range(n), degree):
            new_data.append([hash(tuple(v)) for v in data[:,indicies]])
    return array(new_data).T

from kaggle

machine learning in coding（python）：拼接原始数据；生成高次特征

原文：http://blog.csdn.net/mmc2015/article/details/47405469