Question

我正在尝试对从quandl下载的数据进行重新采样，但是即使看起来是TypeError类型的，也总是抛出datetime64[ns]。

我尝试运行pd.to_datetime(df['Date'])以确保其日期时间类型没有运气。

df = pd.read_pickle('data1')
print(df.Close.head())
df = df.reset_index()
df = df[['Date', 'Close']]
print(df.Date.head())
df = df.resample('W').mean

Date
2004-08-19    100.335
2004-08-20    108.310
2004-08-23    109.400
2004-08-24    104.870
2004-08-25    106.000
Name: Close, dtype: float64
0   2004-08-19
1   2004-08-20
2   2004-08-23
3   2004-08-24
4   2004-08-25
Name: Date, dtype: datetime64[ns]
Traceback (most recent call last):
  File "/Users/raymond.devries/PycharmProjects/untitled2/datatry.py", line 15, in <module>
    df = df.resample('W').mean
  File "/Users/raymond.devries/PycharmProjects/untitled2/venv/lib/python3.7/site-packages/pandas/core/generic.py", line 8155, in resample
    base=base, key=on, level=level)
  File "/Users/raymond.devries/PycharmProjects/untitled2/venv/lib/python3.7/site-packages/pandas/core/resample.py", line 1250, in resample
    return tg._get_resampler(obj, kind=kind)
  File "/Users/raymond.devries/PycharmProjects/untitled2/venv/lib/python3.7/site-packages/pandas/core/resample.py", line 1380, in _get_resampler
    "but got an instance of %r" % type(ax).__name__)
TypeError: Only valid with DatetimeIndex, TimedeltaIndex or PeriodIndex, but got an instance of 'RangeIndex'

Answer 1

错误清楚地表明，重新采样仅对日期索引格式有效，另一方面，您获得了范围索引，例如数据框，首先将索引从范围转换为日期类型数据，删除日期列，然后重新采样将起作用。 / p>

Answer 2

我没有意识到需要将日期时间数据时间设置为索引。重采样功能读取数据帧的索引。数据帧的索引已经设置为日期时间索引，因此不需要运行df = df.reset_index()，因此我将索引变成了范围对象。

工作代码：

df = pd.read_pickle('data1')
df = df[['Close']]
df = df.resample('W').mean()
print(df.head())

输出：

               Close
Date                
2004-08-22  104.3225
2004-08-29  106.8660
2004-09-05  101.2300
2004-09-12  102.8800
2004-09-19  112.4900

Process finished with exit code 0

无法重新采样时间序列数据，TypeError

2 个答案: