如何在Python的Bokeh圆图中添加图例

Question

我有以下代码：

from bokeh.plotting import figure, show, output_file
from bokeh.sampledata.iris import flowers

colormap = {'setosa': 'red', 'versicolor': 'green', 'virginica': 'blue'}
colors = [colormap[x] for x in flowers['species']]

p = figure(title = "Iris Morphology")
p.xaxis.axis_label = 'Petal Length'
p.yaxis.axis_label = 'Petal Width'

p.circle(flowers["petal_length"], flowers["petal_width"],
         color=colors, fill_alpha=0.2, size=10)

output_file("iris.html", title="iris.py example")

show(p)

哪个产生这个情节

如何根据图的圆圈颜色添加图例？哪里：

• setosa：红色
• 杂色：绿色
• 弗吉尼亚：蓝色

Answer 1

想到的最简单的方法是为要向其传递数据的绘图定义ColumnDataSource，然后从此处引用带有 "species"来自数据框的数据。

这是使用此解决方案的代码重做：

from bokeh.plotting import ColumnDataSource, figure, show, output_file
from bokeh.sampledata.iris import flowers

from bokeh.plotting import (ColumnDataSource, figure, show, output_file)
from bokeh.sampledata.iris import flowers

colormap = {'setosa': 'red', 'versicolor': 'green', 'virginica': 'blue'}
colors = [colormap[x] for x in flowers['species']]
flowers['colors'] = colors

source = ColumnDataSource(flowers)

p = figure(title = "Iris Morphology")
p.xaxis.axis_label = 'Petal Length'
p.yaxis.axis_label = 'Petal Width'

p.circle("petal_length", "petal_width",
         color='colors', fill_alpha=0.2, size=10, legend='species',source=source)
p.legend.location = "top_left"

output_file("iris.html", title="iris.py example")

show(p)

这就是您应该获得的。我另外将图例放在右边，这样它就不会插入到图的顶部：