如何从单个数据帧列中减去数组？

Question

我有两个“向量”的数字，我想从中减去一个。我的问题是其中一个是列表的数组：

array([[ 796.24475 ],
      [ -17.138123],
      [ 164.9989  ],
      ...,
      [-469.85388 ],
      [-762.1892  ],
      [-451.34702 ]], dtype=float32)

另一个是数据帧的一列：

0       831.871558
21       26.070256
25      199.351116
28      861.052529
35      113.232070
           ...    
9440   -163.200046
9448   -893.619023
9449   -439.174531
9451   -795.033901
9461   -413.469417
Name: electricity, Length: 1895, dtype: float64 

它们都有相同数量的数据点，当我尝试从另一个数据点减去一个数据点时，得到的误差如下：

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\series.py", line 636, in __array_ufunc__
    self, ufunc, method, *inputs, **kwargs
  File "pandas\_libs\ops_dispatch.pyx", line 91, in pandas._libs.ops_dispatch.maybe_dispatch_ufunc_to_dunder_op
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\ops\common.py", line 64, in new_method
    return method(self, other)
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\ops\__init__.py", line 502, in wrapper
    return _construct_result(left, result, index=left.index, name=res_name)
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\ops\__init__.py", line 475, in _construct_result
    out = left._constructor(result, index=index)
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\series.py", line 305, in __init__
    data = sanitize_array(data, index, dtype, copy, raise_cast_failure=True)
  File "C:\Projects\test\testvenv\lib\site-packages\pandas\core\construction.py", line 482, in sanitize_array
    raise Exception("Data must be 1-dimensional")
Exception: Data must be 1-dimensional

感谢所有帮助，提前感谢

Answer 1

我认为最简单的是选择1d数组（数据帧和数组的长度必须相同）：

df['electricity'] - arr[:, 0]

另一个想法，谢谢@timgeb是使用^{}：

df['electricity'] - arr.squeeze()