djrhails-graphs 0.5.0

Economist-style chart theme for matplotlib/seaborn

graphs

Economist-style chart theme for matplotlib and seaborn — global theme, title-stack finaliser with renderer-measured wrapping, on-grid axis labels, direct line labels, CI bands, and a catalogue of chart helpers (bars, dumbbells, thermometers, bump charts, lollipops). IBM Plex Sans typography and a curated palette.

Install

pip install djrhails-graphs

PyPI distribution is djrhails-graphs because the bare name graphs is taken. The import package is graphs.

Quick start

import matplotlib.pyplot as plt
import numpy as np

from graphs import finalize, label_lines, save_chart, set_theme, subplots

set_theme()

x = np.arange(12)
fig, ax = subplots("wide")
ax.plot(x, 40 + 2.1 * x, label="Series A")
ax.plot(x, 58 - 1.3 * x, label="Series B")
label_lines(ax)
finalize(
    ax,
    title="State the finding, not the topic",
    descriptor="Country, metric, unit",
    source="Source: Organisation",
)
save_chart(__file__)

finalize() does the heavy lifting: auto-sized margins, title stack with the delta marker (titles auto-wrap to the figure width), numeric y labels seated on gridlines that extend under them, source line, right-hand y-axis.

SKILL.md is the full manual — design principles, headline conventions, the complete API table, and a when-to-use index of 39 worked examples in examples/.

Palette

from graphs import PALETTE, colors, C_RED, C_RED_BRAND, C_SPINE, C_GRID, C_LABEL

Nine named colours in PALETTE (red-led default cycle); structural greys for spines/grid/labels/source; cycle_for(chart_type) for per-chart-type orders.

Typography

IBM Plex Sans (headlines) and IBM Plex Sans Condensed (everything else) are loaded automatically. If already registered in matplotlib's font manager, no download occurs. Otherwise TTFs are fetched from github.com/IBM/plex on first use and cached inside the installed package.

Fallback chain: IBM Plex Sans Condensed → IBM Plex Sans → Verdana → Arial → DejaVu Sans.

Development

Hot reload:

uv run graphs-watch

Watches graphs/ and examples/ for .py changes and re-renders the affected examples + comparisons. Tests: uv run --with pytest pytest -q. Reference images for the replica examples: uv run examples/fetch_refs.py, then uv run examples/build_comparisons.py.

License

MIT. See LICENSE.