[ENH]: Automatically trim the time on the x axis

还没有人认领这个 Issue。

### Problem

I would like to have the x-axis showing the timestamps of the samples of audio files. Here is a minimal example:

```
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import dates as mdates
from scipy.io import wavfile

# Open the WAV files
audio_1 = wavfile.read("audio1.wav")
freq_audio_1 = audio_1[0]
samples_1 = audio_1[1][:, 0] # Turn to mono

audio_2 = wavfile.read("audio2.wav")
freq_audio_2 = audio_2[0]
samples_2 = audio_2[1][:, 0] # Turn to mono

# Create the timestamps
t_audio_1 = np.arange(0, len(samples_1)) / freq_audio_1
t_audio_2 = np.arange(0, len(samples_2)) / freq_audio_2

# We turn them into datetime
t_audio_1 = np.array(t_audio_1*1000, dtype="datetime64[ms]")
t_audio_2 = np.array(t_audio_2*1000, dtype="datetime64[ms]")

# Create the figure
fig, ax = plt.subplots(1, 2, constrained_layout=True)

# If the audio files are more than 1 hour, we format as HH:MM:SS, else just MM:SS
if len(samples_1) / freq_audio_1 >= 3600 and len(samples_2) / freq_audio_2 >= 3600 :
formatter = mdates.AutoDateFormatter(mdates.AutoDateLocator(), defaultfmt='%H:%M:%S')
else:
formatter = mdates.AutoDateFormatter(mdates.AutoDateLocator(), defaultfmt='%M:%S')

plt.gcf().axes[0].xaxis.set_major_formatter(formatter)
plt.gcf().axes[1].xaxis.set_major_formatter(formatter)

ax[0].plot(t_audio_1, samples_1)
ax[1].plot(t_audio_2, samples_2)
plt.show()
```
Here is the output:

As you can see, the microsecond precision makes so that the ticks on the x axis are shown on top of each other.

### Proposed solution

The ideal would be to have the plot automatically decide how many significant digits after the comma are necessary, depending on the level of zoom (in a similar fashion to the way Audacity displays timestamps).

Thank you :)

首先重现最小音频时间戳示例，并读取 mdates.AutoDateFormatter 和 mdates.AutoDateLocator 在不同缩放级别下的行为。完成的标准是：x 轴通过选择适当的精度，自动避免时间戳标签重叠，同时仍能为较短和较长的音频范围显示有用的时间信息。

由索引模型根据 Issue 内容生成。