在Streamlit中部署Altair图表时遭遇无法排查的语法错误求助

Hey there! Let's dig into why that syntax error is popping up—your second code block looks identical in structure to the first working one, so the issue is almost certainly not in the line the error is pointing to. Here's what to check:

Common Causes & Fixes #

Since Python's syntax error messages can sometimes point to the next line after the actual mistake, focus on the code immediately before line 90 (where ward_streets_sidewalks = ... starts):

• Unclosed parentheses/brackets/braces: Did you forget to close a (), [], or {} in the lines above? For example, if you had something like st.dataframe(df_ward[['Ward', 'avg_housing_cost_ward'] (missing the closing ]), Python would keep parsing into your next code block, breaking its syntax.
• Unclosed quotes: A missing single quote ', double quote ", or triple quote """/''' in preceding code will turn subsequent lines into part of an unfinished string, triggering a syntax error.
• Indentation issues: Mixed spaces and tabs, or incorrect indentation levels (like a line that's supposed to be indented but isn't, or vice versa) can throw off Python's parser in unexpected ways.

Quick Test to Confirm #

Try temporarily commenting out the entire second chart block:

# ward_streets_sidewalks = alt.Chart(df_ward).mark_bar().encode(
#     alt.X('Ward:N'),
#     alt.Y('avg_streets_sidewalks_ward:Q', title = 'rating of maintenance of streets/sidewalks')
# ).properties(title = 'Rating of maintenance of streets/sidewalks by ward')
# st.altair_chart(ward_streets_sidewalks)

If your app runs without errors now, that confirms the problem is in the code before this block. Go line by line above line 90 to spot the unclosed syntax element.

Also, double-check that avg_streets_sidewalks_ward exists in df_ward—though that would throw a different error (not a syntax error), it's worth verifying just in case.

内容的提问来源于stack exchange，提问作者midnightradi0