182 articles tagged #Debugging
Merging multiple sheets into one with xlsxwriter and ending up with headers sprinkled throughout your data? Here's exactly why that happens and how to write the merge loop that gets it right every time.
Writing datetime objects with xlsxwriter and getting ugly floats like 45123.708333 instead of a readable date? Here's why it happens, what the format object actually does, and how to fix it for good.
You set up data validation dropdowns in xlsxwriter, added sheet protection, opened the file in Excel — and the dropdowns are gone. Here's exactly why that happens and how to fix it without losing your protection settings.
Your useEffect runs twice in development but exactly once in production — and it's not a bug in your code. React's Strict Mode intentionally double-invokes effects to help you catch subtle issues. Here's what's happening and how to handle it correctly.
Your USB-C hub is cutting out mid-presentation or disconnecting your external drive at the worst moment. Here's how to track down exactly what's causing it and get a stable connection back fast.
You've called freeze_panes on every sheet, but when the file opens in Excel only some sheets are frozen—or none at all. Here's exactly why xlsxwriter silently drops the setting and how to fix it for good.
If your Pandas pivot_table is producing numbers that don't match your expectations, the aggregation is probably running on the wrong columns. Here's how to catch it, understand why it happens, and fix it for good.
Seeing duplicate rows in your Power BI visuals when the source data looks clean? The culprit is almost always a misconfigured relationship. Here's how to diagnose and fix it without guessing.
Your read_csv call is crawling on a file that should load in seconds. Before you rewrite your pipeline, check these common culprits — dtype inference, unnecessary columns, and chunking strategy — in the right order.
You define named ranges in xlsxwriter, open the file in Excel, and they're gone. This happens because of a subtle sequencing and scope issue — here's exactly how to fix it and verify your ranges persist.
You added an index, ran your query, and EXPLAIN ANALYZE still shows a sequential scan. Before you blame PostgreSQL, there are at least six specific reasons this happens — and each one has a clear fix.
xlsxwriter's autofit method sets row heights that look right in the preview but end up clipped or oversized in Excel. Here's why it happens and exactly how to calculate correct row heights yourself.