Choropleth us-states map showing incorrect data and color coding - pandas

Question

I am trying to show hospitals by type in US states. The dataset I am using is here https://www.kaggle.com/carlosaguayo/usa-hospitals
I am using choropleth and here is my code. I basically have a dropdown with the type of hospital and when select, I am getting the count
#app.callback(Output('figure-1', 'figure'),
[Input('options-drop', 'value')])
def make_figure(varname):
mygraphtitle = f'Hospitals of {varname}'
mycolorscale = 'Blues'
mycolorbartitle = "Count"
data=go.Choropleth(
locations=df['STATE'],
locationmode = 'USA-states',
z = df[df["TYPE"] == varname]["STATE"].value_counts(),
colorscale = mycolorscale,
colorbar_title = mycolorbartitle,
)
fig = go.Figure(data)
fig.update_layout(
title_text = mygraphtitle,
geo_scope='usa',
width=1200,
height=800
)
return fig
I have 3 issues with the grpah
Data is not being shown for all states
Data shown for few states is incorrect
Color coding is incorrect even for those states with incorrect data. state with higher hospital count is shown with lighter blue whereas with lower count is shown with darker blue
You can see below from pandas, I can tell Texas has only 65 critical access hospitals but the US map shows count as 78 and even if it was 78, the color of Texas is light blue compared with other state with lower hospitals. Where am I going wrong?

Answer 1

I have not verified this in the Dash environment, but I believe the operation will be the same. The cause is that you are specifying a state column for the entire data frame you are setting up. The easiest response is to target the filtered data frame.
import plotly.graph_objects as go
import pandas as pd
df = pd.read_csv('./data/Hospitals.csv')
varname = 'CRITICAL ACCESS'
filtered_df = df[df["TYPE"] == varname]["STATE"].value_counts().to_frame('value')
#print(filtered_df)
fig = go.Figure(data=go.Choropleth(
locations=filtered_df.index,
z = filtered_df['value'],
locationmode = 'USA-states',
colorscale = 'Blues',
colorbar_title = "Count",
))
fig.update_layout(
title_text = f'Hospitals of {varname}',
geo_scope='usa',
width=1200,
height=800
)
fig.show()