从matplotlib样式获取颜色


问题内容

这个问题已经在这里有了答案

获取默认的线条颜色周期
(4个答案)

去年关闭。

我想实现的目标:

我想在一个图上创建多个饼图。它们都共享某些类别,但有时具有不同的类别。显然,我希望所有相同的类别都具有相同的颜色。

这就是为什么我创建了一个将类别(=标签)链接到颜色的字典的原因。这样,我可以指定饼图的颜色。但是我想使用ggplot颜色(与matplotlib.style.style.use(’ggplot’)一起提供)。如何获得这些颜色以将其输入到字典中?

# set colors for labels
color_dict = {}
for i in range(0, len(data_categories)):
    color_dict[data_categories[i]] = ???

# apply colors
ind_label = 0
for pie_wedge in pie[0]:
    leg = ax[ind].get_legend()
    pie_wedge.set_facecolor(color_dict[labels_0[ind_label]])          
    leg.legendHandles[ind_label].set_color_(color_dict[labels_0[ind_label]])
    ind_label += 1

问题答案:

简短答案

要访问ggplot样式中使用的颜色,可以执行以下操作

In [37]: import matplotlib.pyplot as plt

In [38]: plt.style.use('ggplot')

In [39]: colors = plt.rcParams['axes.prop_cycle'].by_key()['color']

In [40]: print('\n'.join(color for color in colors))                                      
#E24A33
#348ABD
#988ED5
#777777
#FBC15E
#8EBA42
#FFB5B8

在上面的示例中,颜色(如RGB字符串)包含在list中colors

plt.style.use(...)在访问颜色列表之前,请记住先致电,否则您将找到标准颜色。


更详细的解释

上面的答案是针对Matplotlib的现代发行版量身定制的,在该版本中,绘图颜色和其他可能的绘图属性(如线宽和破折号(请参阅我的答案))rcParams使用键存储在字典中,'axes.prop_cycle'并包含在一种新的对象中,a
cyclercycler上面引用的我的回答中包含a的其他说明)。

为了获得颜色列表中,我们必须得到cyclerrcParams,然后利用其.by_key()方法

Signature: c.by_key()
Docstring: Values by key

This returns the transposed values of the cycler.  Iterating
over a `Cycler` yields dicts with a single value for each key,
this method returns a `dict` of `list` which are the values
for the given key.

The returned value can be used to create an equivalent `Cycler`
using only `+`.

Returns
-------
transpose : dict
    dict of lists of the values for each key.

拥有一个值字典,最后,我们使用key进行索引'color'


附录

并非绝对必须use('a_style')访问其颜色,颜色(可能)matplotlib.RcParams是在存储在字典中的对象中定义的matplotlib.style.library。例如,让我们打印以不同样式定义的所有颜色序列

In [23]: for style in plt.style.library: 
    ...:     the_rc = plt.style.library[style] 
    ...:     if 'axes.prop_cycle' in the_rc: 
    ...:         colors = the_rc['axes.prop_cycle'].by_key()['color'] 
    ...:         print('%25s: %s'%(style, ', '.join(color for color in colors))) 
    ...:     else: 
    ...:         print('%25s: this style does not modify colors'%style)                                                                          
          dark_background: #8dd3c7, #feffb3, #bfbbd9, #fa8174, #81b1d2, #fdb462, #b3de69, #bc82bd, #ccebc4, #ffed6f
                   ggplot: #E24A33, #348ABD, #988ED5, #777777, #FBC15E, #8EBA42, #FFB5B8
           seaborn-poster: this style does not modify colors
             seaborn-talk: this style does not modify colors
           seaborn-bright: #003FFF, #03ED3A, #E8000B, #8A2BE2, #FFC400, #00D7FF
         seaborn-notebook: this style does not modify colors
         seaborn-darkgrid: this style does not modify colors
                      bmh: #348ABD, #A60628, #7A68A6, #467821, #D55E00, #CC79A7, #56B4E9, #009E73, #F0E442, #0072B2
                     fast: this style does not modify colors
                  seaborn: #4C72B0, #55A868, #C44E52, #8172B2, #CCB974, #64B5CD
            seaborn-white: this style does not modify colors
            _classic_test: b, g, r, c, m, y, k
             seaborn-deep: #4C72B0, #55A868, #C44E52, #8172B2, #CCB974, #64B5CD
            seaborn-paper: this style does not modify colors
                grayscale: 0.00, 0.40, 0.60, 0.70
     seaborn-dark-palette: #001C7F, #017517, #8C0900, #7600A1, #B8860B, #006374
       seaborn-colorblind: #0072B2, #009E73, #D55E00, #CC79A7, #F0E442, #56B4E9
     tableau-colorblind10: #006BA4, #FF800E, #ABABAB, #595959, #5F9ED1, #C85200, #898989, #A2C8EC, #FFBC79, #CFCFCF
             seaborn-dark: this style does not modify colors
                  classic: b, g, r, c, m, y, k
           seaborn-pastel: #92C6FF, #97F0AA, #FF9F9A, #D0BBFF, #FFFEA3, #B0E0E6
            seaborn-ticks: this style does not modify colors
          Solarize_Light2: #268BD2, #2AA198, #859900, #B58900, #CB4B16, #DC322F, #D33682, #6C71C4
        seaborn-whitegrid: this style does not modify colors
            seaborn-muted: #4878CF, #6ACC65, #D65F5F, #B47CC7, #C4AD66, #77BEDB
          fivethirtyeight: #008fd5, #fc4f30, #e5ae38, #6d904f, #8b8b8b, #810f7c

PS-以我的理解

  • seaborn-xxx不修改颜色样式在样式序列来作为最后一步,例如,plt.style.use(['seaborn', 'seaborn-poster'])plt.style.use(['seaborn', 'seaborn-muted', 'seaborn-poster'])
  • 唯一fast不更改颜色的样式就是调整渲染参数以实现 更快的 渲染。