pandas-基础操作

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DataFrame基础操作

创建DataFrame

列表

df = pd.DataFrame([1,3,4,5],index=[5,8,1,4],columns=['a'])

多维列表

df1=pd.DataFrame([[1,2,3],[None,None,2],[None,None,None],[8,8,None]])

字典

df2=pd.DataFrame({'b':[4,7,-3,2],'a':[0,1,0,1]})

numpy

df4=pd.DataFrame(np.arange(9).reshape(3,3),index=['a','c','d'],columns=['oh','te','ca'])

排序DataFrame

sort_index()

df1=pd.DataFrame([1,2,3,4,5],index=[10,52,24,158,112],columns=['s'])
df1.sort_index()

sort_values()

df2=pd.DataFrame({'b':[4,7,-3,2],'a':[0,1,0,1]})
df2.sort_values(by='b')

删除

drop()

删除行

df4=pd.DataFrame(np.arange(9).reshape(3,3),index=['a','c','d'],columns=['oh','te','ca'])
df4.drop('a')

删除列

df4=pd.DataFrame(np.arange(9).reshape(3,3),index=['a','c','d'],columns=['oh','te','ca'])
df4.drop(['oh'],axis=1)

删除None值

dropna()

df1=pd.DataFrame([[1,2,3],[None,None,2],[None,None,None],[8,8,None]])
 df1.dropna()

dropna(how=’all’)

df1=pd.DataFrame([[1,2,3],[None,None,2],[None,None,None],[8,8,None]])
df1.dropna(how='all')

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