I’ve tried StackOverflow and someone mentioned I try here. I have a dataframe and I can make a Choropleth map from each individual data column (% Population Change and Unemployment Rate). I’d like to connect a dropdown to the graph. Like I said, I can create a static Dash Choropleth map from one of the column, but can’t connect the dropdown to the graph.
My stackoverflow question: python - How to connect a Plotly Dash dropdown to a Choropleth map? - Stack Overflow
There’s a bunch of code before to create this DataFrame. Here’s the first five lines.
FIPS Geographic Area State 4/1/2010 Census 4/1/2020 Census % Population Change Unemployment Rate
0 22001 Acadia LA 61787 57576 -6.815350 3.6
1 22003 Allen LA 25747 22750 -11.640191 4.0
2 22005 Ascension LA 107215 126500 17.987222 2.9
3 22007 Assumption LA 23416 21039 -10.151179 5.3
4 22009 Avoyelles LA 42071 39693 -5.652350 3.7
And here’s the rest of the code.
import pandas as pd
import requests
from bs4 import BeautifulSoup
from urllib.request import urlopen
import json
import dash
import plotly.graph_objs as go
import dash_html_components as html
import dash_core_components as dcc
from dash.dependencies import Input, Output
import plotly.express as px
def display_chart():
# There's a bunch of code before this, but the dataframe works fine on separate Choropleth maps. I would like an interactive map using the drop down.
df = pd.merge(df4, df5, on="Geographic Area", how='inner')
# print(df) The output is printed in this forum question.
app = dash.Dash()
app.layout = html.Div([
html.H2('Financial Genome Project'),
dcc.Dropdown(
id='census_type',
options=[{"label": x, "value": x}
for x in df.columns[5:]],
value=df.columns[0],
clearable=False,
style={'width': 300},
placeholder="Select a census data type"
),
html.Hr(),
dcc.Graph(id="choropleth-chart"),
])
@app.callback(
Output("choropleth-chart", "figure"),
[Input("census_type", "value")]
)
def display_choropleth(census_type):
fig = px.choropleth(df, geojson=counties,
locations='FIPS',
color=census_type,
color_continuous_scale="rdylgn_r",
range_color=(0, 8),
scope="usa",
hover_name='Geographic Area',
# labels={'% Change': 'Population % Change'}
)
# fig.update_layout(margin={"r": 0, "t": 0, "l": 0, "b": 0})
fig.update_geos(fitbounds='locations', visible=False)
return fig
app.run_server(debug=True)
display_chart()
This is what I get. No Choropleth map and callback errors.
