[subplot-mosaic] Mosaic Subplot Layout with Varying Sizes

[MarkusNeusinger]

A complex subplot layout where different subplots can have varying sizes and arrangements, enabling custom grid configurations beyond simple row/column grids. Similar to matplotlib's subplot_mosaic or CSS grid layouts.

[claude]

✅ Spec ID: subplot-mosaic

Rationale: Uses the standard naming pattern {type}-{variant} to describe a mosaic-style subplot layout, distinct from existing subplot-grid (uniform grids) and subplot-grid-custom (colspan/rowspan GridSpec). This spec focuses on ASCII-art string definitions for intuitive layout creation.

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: subplot-mosaic

PR: #3009

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specification.md

subplot-mosaic: Mosaic Subplot Layout with Varying Sizes

Description

A complex subplot layout where different subplots can have varying sizes and arrangements using intuitive ASCII-art style string definitions. Unlike GridSpec approaches that require explicit row/column spanning, mosaic layouts allow defining layouts through visual string patterns (e.g., "AB;CC" creates A and B on top, C spanning below), making complex configurations more readable and maintainable.

Applications

• Dashboard layouts with a dominant visualization surrounded by smaller supporting charts
• Scientific figures where related plots need non-uniform visual emphasis
• Multi-panel reports combining wide time series with stacked detail panels
• Exploratory data analysis layouts with flexible panel arrangements

Data

• x (numeric or categorical) - Primary variable for each subplot
• y (numeric) - Secondary variable for each subplot
• z (numeric, optional) - Tertiary variable for color or size encoding
• Size: Varies per subplot, typically 20-500 points per cell
• Example: Dashboard with wide overview chart (top), two medium detail charts (middle), and three small metric panels (bottom)

Notes

• Layout defined using string patterns where repeated characters indicate spanning
• Support patterns like "AAB;AAB;CCC" for complex asymmetric layouts
• Allow empty cells using placeholder characters (e.g., "." for gaps)
• Maintain consistent spacing between all subplots
• Clear visual hierarchy with larger cells for primary data
• Each cell can contain a different plot type (line, bar, scatter, etc.)

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: subplot-mosaic
PR: #3009 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

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🤖 spec-create workflow