dataviz

# Dataviz Use this skill before producing a chart, dashboard, map, or data visualization. ## Workflow 1. Identify the analytic task: comparison, trend, distribution, relationship, ranking, part-to-whole, geography, or status monitoring. 2. Choose the simplest chart form that answers that task. Read `references/choosing-a-form.md` when the form is not obvious. 3. Write the finding into the title, subtitle, axis label, or direct annotation. A viewer should know what changed, what is high or low, or what decision the chart supports. 4. Pick colors from `references/palette.md`, or validate any custom palette with the script below. 5. Check `references/anti-patterns.md` before finalizing the design. ## Palette Validation Resolve paths relative to the skill base directory shown above this skill body. Do not assume `$QWEN_SKILL_ROOT` is set for normal shell commands. Run: ```bash node <skill-base-directory>/scripts/validate_palette.js '#1d4ed8,#b45309,#166534' --mode light ``` Treat `FAIL` as a required palette change. Treat `WARN` as acceptable only when the chart also uses labels, shape, texture, ordering, or another secondary encoding. ## Mark Rules - Use categorical palettes for unordered groups; use sequential or diverging ramps only for ordered values. - Prefer direct labels over legends when the chart has a small number of series. - Keep gridlines subtle and fewer than the data marks. - Avoid dual axes unless both series share a clearly explained transformation. - Do not rely on color alone for critical distinctions. - Keep dashboards scan-friendly: align cards, use consistent number formats, and reserve saturated color for important state changes.