Python OverflowerError:在熊猫系列绘图上格式化日期时，int太大，无法转换

我正在尝试绘制熊猫系列，但在尝试格式化x轴日期时遇到错误

（在评论中发现了一个相关的问题，但它似乎是在比我使用的版本更旧的熊猫版本中解决的。因此，这似乎是一个新问题。）

考虑以下系列的绘图：

import pandas as pd

d = {pd.Timestamp('2021-03-15 08:30:00'): -65.926651,
     pd.Timestamp('2021-03-15 08:30:05'): -42.115551,
     pd.Timestamp('2021-03-15 08:30:10'): -24.699627,
     pd.Timestamp('2021-03-15 08:30:15'): -12.010081,
     pd.Timestamp('2021-03-15 08:30:20'): -2.781321}

s = pd.Series(d)

ax = s.plot()

我试图使用以下方法在绘图上设置x轴日期的格式：

from matplotlib.dates import DateFormatter
format_str: str = '%H:%M:%S'
format_: DateFormatter = DateFormatter(format_str)
ax.xaxis.set_major_formatter(format_)

这将导致以下错误：

      Traceback (most recent call last):
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/backends/backend_macosx.py", line 61, in _draw
    self.figure.draw(renderer)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/artist.py", line 41, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/figure.py", line 1863, in draw
    mimage._draw_list_compositing_images(
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/image.py", line 131, in _draw_list_compositing_images
    a.draw(renderer)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/artist.py", line 41, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/cbook/deprecation.py", line 411, in wrapper
    return func(*inner_args, **inner_kwargs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/axes/_base.py", line 2747, in draw
    mimage._draw_list_compositing_images(renderer, self, artists)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/image.py", line 131, in _draw_list_compositing_images
    a.draw(renderer)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/artist.py", line 41, in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/axis.py", line 1164, in draw
    ticks_to_draw = self._update_ticks()
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/axis.py", line 1022, in _update_ticks
    major_labels = self.major.formatter.format_ticks(major_locs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/ticker.py", line 250, in format_ticks
    return [self(value, i) for i, value in enumerate(values)]
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/ticker.py", line 250, in <listcomp>
    return [self(value, i) for i, value in enumerate(values)]
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/dates.py", line 605, in __call__
    return num2date(x, self.tz).strftime(self.fmt)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/dates.py", line 511, in num2date
    return _from_ordinalf_np_vectorized(x, tz).tolist()
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/numpy/lib/function_base.py", line 2108, in __call__
    return self._vectorize_call(func=func, args=vargs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/numpy/lib/function_base.py", line 2192, in _vectorize_call
    outputs = ufunc(*inputs)
  File "/Users/me/VirtualEnvironments/my_venv/lib/python3.9/site-packages/matplotlib/dates.py", line 331, in _from_ordinalf
    np.timedelta64(int(np.round(x * MUSECONDS_PER_DAY)), 'us'))
OverflowError: int too big to convert

当我在

np.timedelta64

调用中检查

x

时，它对应于自unix纪元（1970年1月1日）开始以来的天数，前提是我将小数部分添加到时间戳中。如果没有小数部分，那么得到的整数是巨大的，并且似乎与1970年1月1日以来的天数没有明显的关系

---

这里怎么了？

发生错误，因为提供的数据超出了DateFormatter处理的数字范围

请参阅

例如，第一个时间序列的实际数据如下所示

s.index[0].value
1615797000000000000

这需要转换为matplotlib可以处理的数字

s.index = mdates.date2num(s.index)
s
18701.354167   -65.926651
18701.354225   -42.115551
18701.354282   -24.699627
18701.354340   -12.010081
18701.354398    -2.781321
dtype: float64

更新（我在3.6.3上，所以我正在修复它。）

---

这是否回答了您的问题？嗯，但是根据这一点，这个错误是在0.15.1（）@SiHa中修复的，我正在使用一个更新版本的pandas:1.1.5。它不是

pandas

。这是

matplotlib

，链接上说这是一个

matplotlib

错误，由

pandas

0.15.0引起，并在

pandas

0.15.1中修复，我不太明白。当存在分数秒分量时，matplotlib似乎可以很好地处理s.index。当存在小数秒时，绘图还具有45度角的时间戳（这是我想要的）

s.index = mdates.date2num(s.index)
s
18701.354167   -65.926651
18701.354225   -42.115551
18701.354282   -24.699627
18701.354340   -12.010081
18701.354398    -2.781321
dtype: float64

ax = s.plot(style='o-')
import matplotlib.dates as mdates
format_str = '%H:%M:%S'
format_ = mdates.DateFormatter(format_str)
ax.xaxis.set_major_formatter(format_)