Py之matplotlib.pyplot：matplotlib.pyplot的plt.legend函数的简介、使用方法之详细攻略

╰半夏微凉° 2023-01-02 05:28 176阅读 0赞

**目录**

matplotlib.pyplot的plt.legend函数的简介

1、参数解释

2、源代码

matplotlib.pyplot的plt.legend函数的使用方法

1、基础用法

--------------------

# matplotlib.pyplot的plt.legend函数的简介 #

legend模块定义了legend类，负责绘制与轴和/或图形相关的图例。Legend类是一个图例句柄和图例文本的容器，该函数是用来给当前图像添加图例内容。大多数用户通常会通过图例函数创建图例。图例处理程序映射指定如何在轴或图形中从artists(线、补丁等)创建图例句柄。默认的图例处理程序定义在legend\_handler模块中。虽然默认的图例处理程序并没有覆盖所有的artists类型，但是可以定义自定义图例处理程序来支持任意对象。

plt.legend(loc='best',frameon=False)    #frameon参数，去掉图例边框
    plt.legend(loc='best',edgecolor='blue') #edgecolor参数，设置图例边框颜色
    plt.legend(loc='best',facecolor='blue') #facecolor参数，设置图例背景颜色,若无边框,参数无效
    plt.legend(["CH", "US"], title='China VS Us')    #设置图例标题
    plt.legend([p1, p2], ["CH", "US"])               #设置图例名字及对应关系

**原始文档**：[https://matplotlib.org/api/legend\_api.html?highlight=legend\#module-matplotlib.legend][https_matplotlib.org_api_legend_api.html_highlight_legend_module-matplotlib.legend]

## 1、参数解释 ##

<table> 
 <tbody> 
 <tr> 
 <td style="width:114px;">参数</td> 
 <td style="width:664px;">解释</td> 
 <td style="width:664px;">具体应用</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">loc</td> 
 <td style="width:664px;"> Location code string, or tuple (see below).图例所有figure位置 </td> 
 <td style="width:664px;">plt.legend(loc='upper center') 0: ‘best' 1: ‘upper right' 2: ‘upper left' 3: ‘lower left' 4: ‘lower right' 5: ‘right' 6: ‘center left' 7: ‘center right' 8: ‘lower center' 9: ‘upper center' 10: ‘center'</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">prop</td> 
 <td style="width:664px;">the font property字体参数</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">fontsize</td> 
 <td style="width:664px;">the font size (used only if prop is not specified)</td> 
 <td style="width:664px;"> fontsize : int or float or {‘xx-small’, ‘x-small’, ‘small’, ‘medium’, ‘large’, ‘x-large’, ‘xx-large’} </td> 
 </tr> 
 <tr> 
 <td style="width:114px;">markerscale</td> 
 <td style="width:664px;">the relative size of legend markers vs. original 图例标记与原始标记的相对大小 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">markerfirst</td> 
 <td style="width:664px;">If True (default), marker is to left of the label. 如果为True，则图例标记位于图例标签的左侧 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">numpoints</td> 
 <td style="width:664px;">the number of points in the legend for line 为线条图图例条目创建的标记点数 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">scatterpoints</td> 
 <td style="width:664px;">the number of points in the legend for scatter plot 为散点图图例条目创建的标记点数 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">scatteryoffsets</td> 
 <td style="width:664px;">a list of yoffsets for scatter symbols in legend 为散点图图例条目创建的标记的垂直偏移量 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">frameon</td> 
 <td style="width:664px;">If True, draw the legend on a patch (frame). 控制是否应在图例周围绘制框架 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">fancybox</td> 
 <td style="width:664px;">If True, draw the frame with a round fancybox. 控制是否应在构成图例背景的FancyBboxPatch周围启用圆边 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">shadow</td> 
 <td style="width:664px;">If True, draw a shadow behind legend. 控制是否在图例后面画一个阴 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">framealpha</td> 
 <td style="width:664px;">Transparency of the frame. 控制图例框架的 Alpha 透明度 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">edgecolor</td> 
 <td style="width:664px;">Frame edgecolor.</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">facecolor</td> 
 <td style="width:664px;">Frame facecolor.</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">ncol</td> 
 <td style="width:664px;">number of columns 设置图例分为n列展示</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">borderpad</td> 
 <td style="width:664px;">the fractional whitespace inside the legend border 图例边框的内边距 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">labelspacing</td> 
 <td style="width:664px;">the vertical space between the legend entries 图例条目之间的垂直间距 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">handlelength</td> 
 <td style="width:664px;">the length of the legend handles&nbsp; 图例句柄的长度 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">handleheight</td> 
 <td style="width:664px;">the height of the legend handles&nbsp; 图例句柄的高度 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">handletextpad</td> 
 <td style="width:664px;">the pad between the legend handle and text&nbsp; 图例句柄和文本之间的间距 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">borderaxespad</td> 
 <td style="width:664px;">the pad between the axes and legend border 轴与图例边框之间的距离 </td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">columnspacing</td> 
 <td style="width:664px;">the spacing between columns&nbsp;列间距</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">title</td> 
 <td style="width:664px;">the legend title</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">bbox_to_anchor</td> 
 <td style="width:664px;">the bbox that the legend will be anchored.指定图例在轴的位置</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 <tr> 
 <td style="width:114px;">bbox_transform</td> 
 <td style="width:664px;">the transform for the bbox. transAxes if None.</td> 
 <td style="width:664px;">&nbsp;</td> 
 </tr> 
 </tbody> 
</table>

## 2、源代码 ##

更新……

def legend Found at: matplotlib.pyplot
    
    @_copy_docstring_and_deprecators(Axes.legend)
    def legend(*args, **kwargs):
        return gca().legend(*args, **kwargs)
    
    # Autogenerated by boilerplate.py.  Do not edit as changes will be lost.

#    matplotlib.pyplot的plt.legend函数的使用方法 #

## 1、基础用法 ##

plt.figure() 
        col_cou_len=len(Keys)
        plt.pie(x=Values,labels=Keys,colors=cols[:col_cou_len], startangle=90,shadow=True,autopct='%1.3f%%') 
        plt.title(tit_name)
        plt.legend()
        plt.show()

[https_matplotlib.org_api_legend_api.html_highlight_legend_module-matplotlib.legend]: https://matplotlib.org/api/legend_api.html?highlight=legend#module-matplotlib.legend