关于python：如何重置pandas数据框中的索引？

How to reset index in a pandas data frame?

我有一个数据帧，从中删除一些行。因此，我得到了一个数据帧，其中索引类似于：[1,5,6,10,11]，我想将其重置为[0,1,2,3,4]。我该怎么做？

以下内容似乎有效：

1 2	df = df.reset_index() del df['index']

以下内容不起作用：

1	df = df.reindex()

你要找的是reset_index()。如果不希望将其保存为列，请执行以下操作：

1	df = df.reset_index(drop=True)

相关讨论

另一种解决方案是分配RangeIndex或range：

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

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

速度更快：

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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