Plotly Express：您可以在 px.choropleth 中手动定义图例吗？

Question

我正在制作px.choropleth()图表plotly.express。

这是代码片段；

import psycopg2

import pandas as pd

import plotly.express as px

''' PostgreSQL Variables '''

# your postgres login variables

''' PostgreSQL Connection '''

# your postgres connection code

''' SQL Query '''

# your SQL Query 

''' Load SQL Queries into Pandas DataFrame '''

African = pd.DataFrame(SQL_Query_Code,

                       columns=['list-of-all-columns'])

''' Variable for Personal Colours '''

# e.g. HTML/HEx code : '#4c5c73'

# List all of the shades/tints codes; in this example I am using the tints codes

my_color_scale = [[0.0, '#4c5c73'], [0.1, '#5D6C81'], [0.2, '#6F7C8F'], [0.3, '#818C9D'], [0.4, '#939DAB'],

                  [0.5, '#A5ADB9'], [0.6, '#B7BDC7'], [0.7, '#C9CED5'], [0.8, '#DBDEE3'], [0.9, '#EDEEF1'],

                  [1.0, '#FFFFFF']]

''' Plotly graph '''

# Government Respond - School Closing

african_figure1 = px.choropleth(African,

                                locations='countrycode',

                                color='c1_school_closing',

                                color_continuous_scale=my_color_scale,

                                range_color=[0, 3],

                                hover_data={'c1_school_closing': False,

                                            'countrycode': False,

                                            'countryname': False},

                                hover_name='countryname',

                                labels={'c1_school_closing': 'SCALE'})

是否可以手动重命名由 ? 自动创建的图例px.choropleth？

Answer 1

我举个例子。coloraxis_colorbar您可以在更新布局中使用字典。这里，tickvals- 颜色条中的枚举值ticktext- 根据值显示的文本from urllib.request import urlopenimport jsonwith urlopen('https://raw.githubusercontent.com/plotly/datasets/master/geojson-counties-fips.json') as response:    counties = json.load(response)import pandas as pddf = pd.read_csv("https://raw.githubusercontent.com/plotly/datasets/master/fips-unemp-16.csv",                   dtype={"fips": str})import plotly.express as pxfig = px.choropleth(df, geojson=counties, locations='fips', color='unemp',                           color_continuous_scale="Viridis",                           range_color=(0, 12),                           scope="usa"                          )fig.update_layout(margin={"r":0,"t":0,"l":0,"b":0},coloraxis_colorbar=dict(    title="unemployment rate",    thicknessmode="pixels",    lenmode="pixels",    yanchor="top",y=1,    ticks="outside",    tickvals=[0,4,8,12],    ticktext=["Low", "Low Medium", "High Medium", "High"],    dtick=4))fig.show()现在来解决你的问题，使用tickvals=[0,1,2,3]和ticktext=['0 - no measures', '1 - recommend closing', '2 - require closing (only some levels)', '3 - require closing all levels']