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Everything you need to level up your coding skills.

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Excel

Data Validation Lists and Their Limits in Excel Sheets

How Excel data validation lists behave and where they stop: the 255 character typed list, range sources, long lists, dependent dropdowns and pasting.

7 min read

ExcelGuide

Controlling What Goes Into a Spreadsheet Before It Spreads

Control what goes into a shared spreadsheet: templates, data validation, tables, protection, error flags and import checks that stop bad data at the source.

17 min read

Excel

Avoiding Misleading Axes in Excel Charts Built From Data

Avoid misleading axes in Excel charts: start bars at zero, set scales on purpose, avoid dual axes, use consistent scales across charts and label the units.

7 min read

Excel

Exporting Excel Charts as Images From a Script or Server

Export charts as PNG or SVG from a script: draw with matplotlib from the same data, render headless with LibreOffice, or use Windows COM.

6 min read

Excel

Building Dashboards in Excel From SQL Output Step by Step

Build an Excel dashboard from SQL output: one data sheet per query, a presentation sheet of tiles and charts, scheduled refresh and tie-out checks.

7 min read

Excel

Sparklines and Conditional Formatting for Quick Scans

Add sparklines, data bars, color scales and icon sets to a table so readers can scan 40 rows in seconds, written from XlsxWriter with accessible choices.

7 min read

Excel

Refreshing Charts From a Changing Data Range in Excel

Fix charts that miss new rows or show blank gaps when data size changes: Excel tables, dynamic named ranges, generated ranges and refresh settings.

7 min read

YAML

Diffing YAML Files Without Whitespace Noise or Reordering

diff -w hides YAML indentation changes that alter meaning. Normalize both files with yq sort_keys and compare as data to ignore layout and order only.

6 min read

YAML

Merging YAML Files From the Command Line With yq Safely

Deep-merge a base and an override with yq eval-all, choose whether lists replace or append, and check what a null or an empty value in the override does.

6 min read