我有一个 2D 的 Numpy 数组,我想将它放在 pandas 的 Series 中(而不是 DataFrame):
>>> import pandas as pd
>>> import numpy as np
>>> a = np.zeros((5, 2))
>>> a
array([[ 0., 0.],
[ 0., 0.],
[ 0., 0.],
[ 0., 0.],
[ 0., 0.]])
但是这会引发一个错误:
>>> s = pd.Series(a)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/miniconda/envs/pyspark/lib/python3.4/site-packages/pandas/core/series.py", line 227, in __init__
raise_cast_failure=True)
File "/miniconda/envs/pyspark/lib/python3.4/site-packages/pandas/core/series.py", line 2920, in _sanitize_array
raise Exception('Data must be 1-dimensional')
Exception: Data must be 1-dimensional
通过黑客手段是可能的:
>>> s = pd.Series(map(lambda x:[x], a)).apply(lambda x:x[0])
>>> s
0 [0.0, 0.0]
1 [0.0, 0.0]
2 [0.0, 0.0]
3 [0.0, 0.0]
4 [0.0, 0.0]
有更好的方法吗?