pandas dataframe 添加行和列

import numpy as np
import pandas as pd

df=pd.DataFrame(np.random.randn(3,4),columns=list("ABCD"),index=list("xyz"))
# print(df)
res1=df.apply(lambda x:x.sum())
# print(res1)
# print(type(res1))  #<class 'pandas.core.series.Series'>

#添加行
df.loc['newrow']=res1
# print(df)
#添加列
res2=df.apply(lambda x:x.sum(),axis=1)
# print(res2)
df['newcolumn']=res2
# print(df)

'''
apply 函数    官网
'''

df = pd.DataFrame([[4, 9],] * 3, columns=['A', 'B'])


# print(df.apply(np.sqrt))
df[['new1','new2']]=df.apply(np.sqrt)
print(df)

# df.loc['newr1','newr2','new3']= df.apply(np.sqrt,axis=1)



res=df.apply(np.sqrt,axis=1)  #<class 'pandas.core.frame.DataFrame'>
print(res)
df=pd.concat([res,df])
print(df)