如何在全息图中设置散射圆半径

Question

简单问题-在散焦图中，您可以用半径而不是大小绘制圆，以便在放大或缩小时调整圆。有可能用基于全息图的散射来实现这一点吗？它目前没有设置半径的选项，我也不知道如何以另一种方式提供它(例如渲染(。可能是用户错误，所以提前道歉，非常感谢。

import holoviews as hv
hv.extension('bokeh')
from bokeh.plotting import figure, show
x=(1,2,3)
y=(1,2,3)
p=figure()
p.scatter(x, y, radius=0.2)
show(p) # bokeh plot working as expected
scatter=hv.Scatter((x,y)).opts(marker="circle", size=20)
scatter # holoviews plot, cannot code "radius" for code above - causes error.

Answer 1

所有hv.Scatter图都基于Bokeh的Scatter标记，该标记在其文档字符串中有此部分：

Note that circles drawn with `Scatter` conform to the standard Marker
interface, and can only vary by size (in screen units) and *not* by radius
(in data units). If you need to control circles by radius in data units,
you should use the Circle glyph directly.

这意味着你不能使用hv.Scatter，你必须使用其他东西：

import holoviews as hv
import param
from holoviews.element.chart import Chart
from holoviews.plotting.bokeh import PointPlot
hv.extension('bokeh')
x = (1, 2, 3)
y = (1, 2, 3)

class Circle(Chart):
group = param.String(default='Circle', constant=True)
size = param.Integer()

class CirclePlot(PointPlot):
_plot_methods = dict(single='circle', batched='circle')
style_opts = ['radius' if so == 'size' else so for so in PointPlot.style_opts if so != 'marker']

hv.Store.register({Circle: CirclePlot}, 'bokeh')
scatter = Circle((x, y)).opts(radius=0.5)