Matplotlib xticks MemoryError

Question

我有一个用时间戳(H:m:s)字符串填充的列表(time)，还有一个用数字填充的列表(number)。两个列表的长度相同，接近350,000个元素。

绘图不是问题，一切都很顺利，但问题出现在添加线条时

plt.xticks(range(len(number)), time, rotation=90, size='small')

我的脚本失败了，因为

Traceback (most recent call last):
  File "G:\Documents\work\program.py", line 114, in <module>
    plt.xticks(range(len(number)), time, rotation=90, size='small')
  File "C:\Python27\lib\site-packages\matplotlib\pyplot.py", line 1674, in xticks
    locs = ax.set_xticks(args[0])
  File "C:\Python27\lib\site-packages\matplotlib\axes\_base.py", line 2850, in set_xticks
    ret = self.xaxis.set_ticks(ticks, minor=minor)
  File "C:\Python27\lib\site-packages\matplotlib\axis.py", line 1606, in set_ticks
    return self.get_major_ticks(len(ticks))
  File "C:\Python27\lib\site-packages\matplotlib\axis.py", line 1294, in get_major_ticks
    tick = self._get_tick(major=True)
  File "C:\Python27\lib\site-packages\matplotlib\axis.py", line 1675, in _get_tick
    return XTick(self.axes, 0, '', major=major, **tick_kw)
  File "C:\Python27\lib\site-packages\matplotlib\axis.py", line 154, in __init__
    self.label1 = self._get_text1()
  File "C:\Python27\lib\site-packages\matplotlib\axis.py", line 372, in _get_text1
    horizontalalignment=horiz,
MemoryError

这对于matplotlib来说真的太多了吗？还是我做错了什么？(除了使用Windows)

Answer 1

我猜，350,000个滴答声只会产生一条宽线。一个接一个地写350,000个字符串也会创建很难读懂的标签。

每10000个刻度和数字尝试一次：

plt.xticks(range(len(number))[::10000], time[::10000], rotation=90, size='small')

使步骤逐渐变小，以查看哪些步骤仍然可读。

要使缩放生效，请使用plt.AutoLocator()

ax = plt.gca() # or use the reference to the axes you already have
ax.xaxis.set_major_locator(plt.AutoLocator())