如何使用Bokeh在绘图上显示各种悬停标识符？

Question

如果我们选择this geographic example from Bokeh documentation，我们会看到当您将鼠标悬停在县上时，德州郡名称会显示在文本框中，以及失业率和经度和纬度。

除了Name之外，我们如何将多个其他标识符添加到该文本框中？为了简单起见，为了论证，我们假设您有Mayor和{{ 1}}作为数据，并希望在Largest Town下显示它们。以上示例中的代码为例，说我们有类似的东西（请参阅所有代码的链接，我只是在这里使用示例）

Name

虽然这不起作用，因为... county_xs = [county["lons"] for county in counties.values()] county_ys = [county["lats"] for county in counties.values()] county_mayor = [county['mayor'] for county in counties.values()] source = ColumnDataSource(data=dict( x=county_xs, y=county_ys, name=county_names, identifier_2 = county_mayor # guessing here rate=county_rates, )) ... hover = p.select_one(HoverTool) hover.point_policy = "follow_mouse" hover.tooltips = [ ("Name", "@name"), ("Unemployment rate)", "@rate%"), ("Mayor", "@identifier_2"), # guessing here ("(Long, Lat)", "($x, $y)"), ] 未知/未定义。

Answer 1

如何继续

您可以先将其他变量的引用添加到悬停工具，方法是先将它们传递给ColumnDataSource。

1. 首先将数据添加到ColumnDataSource（确保变量与其他变量具有相同的维度）
2. 将来源添加到您的图中
3. 之后在悬停工具中引用它

代码

from bokeh.io import show
from bokeh.models import (
    ColumnDataSource,
    HoverTool,
    LogColorMapper
)
from bokeh.palettes import Viridis6 as palette
from bokeh.plotting import figure

from bokeh.sampledata.us_counties import data as counties
from bokeh.sampledata.unemployment import data as unemployment

palette.reverse()

counties = {
    code: county for code, county in counties.items() if county["state"] == "tx"
}

county_xs = [county["lons"] for county in counties.values()]
county_ys = [county["lats"] for county in counties.values()]
# Creating a fake mayor variable
county_mayor = ["Mayor of " + county["name"]  for county in counties.values()]

county_names = [county['name'] for county in counties.values()]
county_rates = [unemployment[county_id] for county_id in counties]
color_mapper = LogColorMapper(palette=palette)

# We add the mayor variable
source = ColumnDataSource(data=dict(
    x=county_xs,
    y=county_ys,
    name=county_names,
    rate=county_rates,
    mayor=county_mayor,
))

TOOLS = "pan,wheel_zoom,reset,hover,save"

p = figure(
    title="Texas Unemployment, 2009", tools=TOOLS,
    x_axis_location=None, y_axis_location=None
)
p.grid.grid_line_color = None

p.patches('x', 'y', source=source,
          fill_color={'field': 'rate', 'transform': color_mapper},
          fill_alpha=0.7, line_color="white", line_width=0.5)

hover = p.select_one(HoverTool)
hover.point_policy = "follow_mouse"
# And we reference the mayor in the tooltip
hover.tooltips = [
    ("Name", "@name"),
    ("Unemployment rate)", "@rate%"),
    ("(Long, Lat)", "($x, $y)"),
    ("Mayor", "@mayor")
]

show(p)    

<强>输出

预期结果应该是这样的：

<强>参考

此link from the documentation处的悬停工具参考。