Plotly Choropleth地图无法填充数据问题求助

Here are the most common fixes for your blank map issue:

• Ensure state abbreviations are uppercase: Plotly's locationmode='USA-states' strictly requires uppercase 2-letter state codes (e.g., 'CA', 'TX'). Mixed or lowercase codes won't be recognized. Fix this with:

  df['state'] = df['state'].str.upper()
  

• Validate state codes for errors: Check for missing values, typos, or non-standard abbreviations (like 'NYC' instead of 'NY'). Use this to inspect unique state values:

  print(df['state'].unique())
  

  Filter out any invalid entries before plotting.

• Double-check parameter mappings: Confirm your px.choropleth call correctly maps columns to parameters:

  fig = px.choropleth(
      df,
      locations='state',  # Must match your state column name exactly
      locationmode='USA-states',
      color='Users',      # Must match your user count column name
      scope='usa'
  )
  

• Verify non-zero user counts: If all values in the Users column are zero, the map will appear blank (no color variation). Check with:

  print(df['Users'].describe())
  

• Update Plotly: Older versions of Plotly might have bugs with US state choropleths. Update to the latest version:

  pip install --upgrade plotly
  

Example Corrected Code #

import plotly.express as px
import pandas as pd

# Load data
df = pd.read_csv('your_data.csv')

# Clean state codes
df['state'] = df['state'].str.upper()
df = df[df['state'].str.len() == 2]  # Filter out invalid codes

# Create map
fig = px.choropleth(
    df,
    locations='state',
    locationmode='USA-states',
    color='Users',
    scope='usa',
    title='US State User Counts'
)
fig.show()

内容的提问来源于stack exchange，提问作者Alex