Python Matplotlib.colors.to_rgb()用法及代码示例

Matplotlib是Python中令人惊叹的可视化库，用于二维阵列图。 Matplotlib是一个基于NumPy数组构建的multi-platform数据可视化库，旨在与更广泛的SciPy堆栈配合使用。

matplotlib.colors.to_rgb()

的matplotlib.colors.to_rgb()函数用于将c(即颜色)转换为RGB颜色。它将颜色名称转换为RGB编码颜色的数组。它从0-1返回三个浮点数的RGB元组。

用法： matplotlib.colors.to_rgb(c)

参数：

c:这接受一个代表颜色名称的字符串。它可以是RGB或RGBA序列或多种形式的字符串：
1. 十六进制颜色字符串，例如“＃000FFF”
2. 标准名称，例如“绿色”
3. 组合“ rgbcmykw”中的一封信
4. 浮点数的字符串表示形式，例如“ 0.4”，表示0-1比例为灰色

范例1：

import matplotlib.pyplot as plt 
import matplotlib.colors as mcolors 
  
  
# helper function to plot a color table 
def colortable(colors, title, colors_sort = True, emptycols = 0):
   
    # cell dimensions 
    width = 212
    height = 22
    swatch_width = 48
    margin = 12
    topmargin = 40
   
    # Sorting colors bbased on hue, saturation, 
    # value and name. 
    if colors_sort is True:
        to_hsv = sorted((tuple(mcolors.rgb_to_hsv(mcolors.to_rgb(color))), 
                         name) 
                        for name, color in colors.items()) 
          
        names = [name for hsv, name in to_hsv] 
          
    else:
        names = list(colors) 
   
    length_of_names = len(names) 
    length_cols = 4 - emptycols 
    length_rows = length_of_names // length_cols + int(length_of_names % length_cols > 0) 
   
    width2 = width * 4 + 2 * margin 
    height2 = height * length_rows + margin + topmargin 
    dpi = 72
   
    figure, axes = plt.subplots(figsize =(width2 / dpi, height2 / dpi), dpi = dpi) 
    figure.subplots_adjust(margin / width2, margin / height2, 
                        (width2-margin)/width2, (height2-topmargin)/height2) 
      
    axes.set_xlim(0, width * 4) 
    axes.set_ylim(height * (length_rows-0.5), -height / 2.) 
    axes.yaxis.set_visible(False) 
    axes.xaxis.set_visible(False) 
    axes.set_axis_off() 
    axes.set_title(title, fontsize = 24, loc ="left", pad = 10) 
   
    for i, name in enumerate(names):
          
        rows = i % length_rows 
        cols = i // length_rows 
        y = rows * height 
   
        swatch_start_x = width * cols 
        swatch_end_x = width * cols + swatch_width 
        text_pos_x = width * cols + swatch_width + 7
   
        axes.text(text_pos_x, y, name, fontsize = 14, 
                horizontalalignment ='left', 
                verticalalignment ='center') 
   
        axes.hlines(y, swatch_start_x, swatch_end_x, 
                  color = colors[name], linewidth = 18) 
   
    return figure 
   
colortable(mcolors.BASE_COLORS, "Base Colors", 
                colors_sort = False, emptycols = 1) 
colortable(mcolors.TABLEAU_COLORS, "Tableau Palette", 
                colors_sort = False, emptycols = 2) 
colortable(mcolors.CSS4_COLORS, "CSS Colors") 
   
plt.show()

输出：

范例2：

from matplotlib import colors 
import matplotlib.pyplot as plt 
  
  
alpha = 0.5
  
kwargs = dict(edgecolors ='none', s = 3900, marker ='s') 
  
for i, color in enumerate(['pink', 'brown', 'green']):
  
    rgb = colors.to_rgb(color) 
    plt.scatter([i], [0], color = color, **kwargs) 
    plt.scatter([i], [1], color = color,  
                alpha = alpha, **kwargs) 
    plt.scatter([i], [2], color = rgb, **kwargs)

输出：

注：本文由纯净天空筛选整理自RajuKumar19大神的英文原创作品 Matplotlib.colors.to_rgb() in Python。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。