pandas docs

• 根据某一列的值进行筛选axis=0

train = pd.read_csv('../input/train.csv')
train.head()

train = pd.read_csv(‘../input/train.csv’)

我们筛选name=”harry”的行

train.loc[data['name'] = 'harry']

• 使用max()查找索引轴上的最大值

import pandas as pd 
df = pd.DataFrame({"A":[12, 4, 5, 44, 1], 
                   "B":[5, 2, 54, 3, 2], 
                   "C":[20, 16, 7, 3, 8],  
                   "D":[14, 3, 17, 2, 6]}) 
df 

默认axis = 0
df.max(axis = 0) 

• 根据某一列的值进行筛选axis=1

df = pd.DataFrame({"A":[12, 4, 5, None, 1],  
                   "B":[7, 2, 54, 3, None], 
                   "C":[20, 16, 11, 3, 8], 
                   "D":[14, 3, None, 2, 6]}) 
//skip the Na values while finding the maximum 
df.max(axis = 1, skipna = True) 

• 按照某一列的值，画直方图，统计各个值的分布情况

import matplotlib.pyplot as plt
train['none'].value_counts().plot.bar()
plt.show()