如何降低 matplotlib 中的孵化密度 [英] How to decrease hatch density in matplotlib

问题描述

我需要降低用 matplotlib 制作的条形图中的阴影密度.我添加舱口的方式:

I need to decrease the density of the hatch in a bar made with matplotlib. The way I add the hatches:

kwargs = {'hatch':'|'}
rects2 = ax.bar(theta, day7, width,fill=False, align='edge', alpha=1, **kwargs)

kwargs = {'hatch':'-'}
rects1 = ax.bar(theta, day1, width,fill=False, align='edge', alpha=1, **kwargs)

我知道您可以通过向模式添加更多字符来增加密度，但是如何降低密度?！

I know that you can increase the density by adding more characters to the pattern, but how can you decrease the density?!

推荐答案

这是一个完整的 hack，但它应该适用于您的场景.

This is a complete hack, but it should work for your scenario.

基本上，您可以定义一个新的填充图案，输入图案越长，填充图案的密度就越低.我已经为您修改了 Horizo​​ntalHatch 模式(注意下划线字符的使用):

Basically, you can define a new hatch pattern that becomes less dense the longer the input string. I've gone ahead and adapted the HorizontalHatch pattern for you (note the use of the underscore character):

class CustomHorizontalHatch(matplotlib.hatch.HorizontalHatch):
    def __init__(self, hatch, density):
        char_count = hatch.count('_')
        if char_count > 0:
            self.num_lines = int((1.0 / char_count) * density)
        else:
            self.num_lines = 0
        self.num_vertices = self.num_lines * 2

然后，您必须将其添加到可用的填充图案列表中:

You then have to add it to the list of available hatch patterns:

matplotlib.hatch._hatch_types.append(CustomHorizontalHatch)

在您的绘图代码中，您现在可以使用定义的模式:

In your plotting code you can now use the defined pattern:

kwargs = {'hatch':'_'}  # same as '-'
rects2 = ax.bar(theta, day7, width,fill=False, align='edge', alpha=1, **kwargs)

kwargs = {'hatch':'__'}  # less dense version
rects1 = ax.bar(theta, day1, width,fill=False, align='edge', alpha=1, **kwargs)

请记住，这不是一个非常优雅的解决方案，并且可能会在未来版本中随时中断.同样，我的模式代码也只是一个快速的技巧，您可能需要对其进行改进.我继承自 Horizo​​ntalHatch ，但要获得更大的灵活性，您可以在 HatchPatternBase 上构建.

Bear in mind that this is not a very elegant solution and might break at any time in future versions. Also my pattern code is just a quick hack as well and you might want to improve on it. I inherit from HorizontalHatch but for more flexibility you would build on HatchPatternBase.

这篇关于如何降低 matplotlib 中的孵化密度的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！