Markers, line styles and panel labels

Markers and dash patterns that stay distinguishable at journal sizes, a cycler that pairs them with colours, and panel labels. See Markers, line styles and panel labels for the guide.

Markers and line styles

plotastro.MARKERS: list[str]

A marker sequence that stays distinguishable at small sizes:

["o", "s", "^", "D", "v", "p", "*", "X"]

plotastro.LINESTYLES: dict[str, str | tuple]

Named dash patterns beyond matplotlib’s built-ins. The tuples are matplotlib (offset, (on, off, ...)) dash specs, which scale with the line width and print cleanly. Use them as ls=pa.LINESTYLES["long dash"].

{"solid": "-",
 "dashed": (0, (5, 2)),
 "dotted": (0, (1, 1.5)),
 "dashdot": (0, (5, 2, 1, 2)),
 "long dash": (0, (9, 3)),
 "dash dot dot": (0, (5, 2, 1, 2, 1, 2)),
 "densely dotted": (0, (1, 0.8)),
 "loosely dashed": (0, (5, 6))}

plotastro.show_markers()

Reference chart of MARKERS (first row) and eight more matplotlib markers, each with the code that draws it.

Return type:

Figure

plotastro.show_linestyles()

Reference chart of the named dash patterns in LINESTYLES.

Return type:

Figure

Cycling colours, markers and dashes together

plotastro.style_cycler(n=None, *, colors=True, markers=False, linestyles=False)

Build a property cycler that pairs colours with markers and/or dash patterns, so lines stay distinguishable in greyscale and for colour-blind readers (redundant encoding).

Parameters:

• n (int, optional) – Number of entries (default: length of the colour cycle, or 8 when markers/linestyles are included).

• colors (bool) – Which properties to cycle together.

• markers (bool) – Which properties to cycle together.

• linestyles (bool) – Which properties to cycle together.

Returns:

• cycler.Cycler (for ax.set_prop_cycle or)

• plt.rc("axes", prop_cycle=...). The colours are always the

• default cycle, COLORS.

Examples

>>> ax.set_prop_cycle(pa.style_cycler(markers=True))
>>> ax.set_prop_cycle(pa.style_cycler(linestyles=True))
>>> plt.rc("axes", prop_cycle=pa.style_cycler(markers=True))  # globally

To pair markers with colours from another palette, build the cycle yourself, e.g. plt.cycler(color=pa.cmasher_colors("torch", n=4)) + plt.cycler(marker=pa.MARKERS[:4]).

Panel labels

plotastro.label_panels(axes, fmt='({})', loc='upper left', uppercase=False, labels=None, **text_kw)

Stamp (a), (b), (c), … on a grid of subplots, the way most journals want multi-panel figures labelled.

Parameters:

• axes (Axes, sequence of Axes, or array from plt.subplots) – Labelled in the order given (arrays are flattened row-major).

• fmt (str, optional) – Applied to each letter; e.g. "({})" -> “(a)”, "{}." -> “a.”.

• loc (str, optional) – One of “upper left”, “upper right”, “lower left”, “lower right”, or “outside” (above the top-left corner — the Nature convention, usually combined with fmt="{}" and bold text).

• uppercase (bool, optional) – Use A, B, C instead of a, b, c.

• labels (sequence of str, optional) – Explicit labels, overriding the alphabet.

• **text_kw – Forwarded to ax.text (e.g. fontweight="bold").

Return type:

list of the Text objects created.

Examples

>>> fig, axes = pa.subplots(2, 2, width="full")
>>> pa.label_panels(axes)
>>> pa.label_panels(axes, loc="outside", fmt="{}", fontweight="bold")