如何在熊猫数据帧中重置索引?

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我有一个数据框架,从其中删除一些行。因此,我得到了一个数据框架,其中索引是这样的:[1,5,6,10,11]我想把它重置为[0,1,2,3,4].我该怎么做?

以下几点似乎有效:

df = df.reset_index()
del df['index']

以下内容不起作用:

df = df.reindex()
提问于
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reset_index(),如果不希望将其保存为列,请执行以下操作:

df = df.reset_index(drop=True)
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另一个解决方案被分配。RangeIndexrange:

df.index = pd.RangeIndex(len(df.index))

df.index = range(len(df.index))

它更快:

df = pd.DataFrame({'a':[8,7], 'c':[2,4]}, index=[7,8])
df = pd.concat([df]*10000)
print (df.head())

In [298]: %timeit df1 = df.reset_index(drop=True)
The slowest run took 7.26 times longer than the fastest. This could mean that an intermediate result is being cached.
10000 loops, best of 3: 105 µs per loop

In [299]: %timeit df.index = pd.RangeIndex(len(df.index))
The slowest run took 15.05 times longer than the fastest. This could mean that an intermediate result is being cached.
100000 loops, best of 3: 7.84 µs per loop

In [300]: %timeit df.index = range(len(df.index))
The slowest run took 7.10 times longer than the fastest. This could mean that an intermediate result is being cached.
100000 loops, best of 3: 14.2 µs per loop

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