使用Pandas数据框索引作为Matplotlib图中x轴的值 [英] Using a Pandas dataframe index as values for x-axis in matplotlib plot

问题描述

我在Pandas dateframe中有一个时间序列，其中有很多列我想绘制.有没有一种方法可以将x轴设置为始终使用dateframe中的索引? 当我使用Pandas的.plot()方法时，x轴的格式正确，但是当我传递日期和列时，我想直接绘制到matplotlib上，所以该图无法正确绘制.预先感谢.

I have time series in a Pandas dateframe with a number of columns which I'd like to plot. Is there a way to set the x-axis to always use the index from a dateframe? When I use the .plot() method from Pandas the x-axis is formatted correctly however I when I pass my dates and the column(s) I'd like to plot directly to matplotlib the graph doesn't plot correctly. Thanks in advance.

plt.plot(site2.index.values, site2['Cl'])
plt.show()

仅供参考:site2.index.values生成了此文件(为简洁起见，我将中间部分切除了):

FYI: site2.index.values produces this (I've cut out the middle part for brevity):

array([
    '1987-07-25T12:30:00.000000000+0200',
    '1987-07-25T16:30:00.000000000+0200',
    '2010-08-13T02:00:00.000000000+0200',
    '2010-08-31T02:00:00.000000000+0200',
    '2010-09-15T02:00:00.000000000+0200'
], 
dtype='datetime64[ns]')

推荐答案

似乎问题出在我有.values.没有它(即site2.index)，图形将正确显示.

It seems the issue was that I had .values. Without it (i.e. site2.index) the graph displays correctly.

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