使用StringIndexer fit报错求助：分类变量转数值变量遇问题

Hey there! I’ve been there—following the official docs step by step only to hit a roadblock with StringIndexer can be super frustrating. To help pinpoint exactly what’s going wrong, could you share a few key pieces of info?

• Full error message: Copy-paste the exact error text you’re seeing, including any stack trace snippets. Common issues here might be things like missing values in your input column, unseen categorical labels during transformation, or typos in column names.
• Your code snippet: Wrap your full StringIndexer-related code in backticks so we can check things like:
  • Did you correctly specify inputCol and outputCol?
  • Are you calling fit() on the right DataFrame before transform()?
  • Did you accidentally pass a non-string column as input?
• Spark version confirmation: Even though you referenced 2.1.0 docs, sometimes there are subtle differences between versions that could cause issues.
• Sample input data: Share a few anonymized rows of your input DataFrame so we can check the structure of your categorical variable.

Once you provide these details, we can dive right into fixing the problem!

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