nice_ticks — ANNOTATE plot op

• Data kinds: none → signal (an op determined by its arguments alone — it takes no image or data input)

• Call: import fullseye as fs; fs.ledger.nice_ticks(lo, hi, n=5, scale='linear') (to call the implementation directly, import annotate; annotate.nice_ticks(lo, hi, n=5, scale='linear'); from the registry, opsannotate.get("nice_ticks"))

Usage

"Round" tick values covering [lo, hi] (1/2/5 × 10^k, closed form).

The ends are included (if lo or hi falls exactly on a tick, it always appears). To avoid the off-by-one where floating-point rounding drops 1 end, the test uses a tolerance of step*1e-9.

With scale='log' it returns decade steps of 1/2/5 × 10^k (placing equally spaced ticks on a log axis squashes them more and more towards the right until they are unreadable).

Raises

ValueError

lo == hi, non-finite, n < 1, lo or hi at or below 0 with log.

Detailed usage guide

• figure_annotation family guide

Background guides (the physics and conventions behind this op)

• dataset_conventions — Training-dataset conventions — COCO / YOLO / VOC and pitfalls in visual inspection

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• annotate_gallery — py -3.11 examples/annotate_gallery.py

• poc_dehazing — py -3.11 examples/poc_dehazing.py

• poc_driving_decisions — py -3.11 examples/poc_driving_decisions.py

• poc_driving_traffic — py -3.11 examples/poc_driving_traffic.py

• poc_measurement_system_analysis — py -3.11 examples/poc_measurement_system_analysis.py

• poc_pxrd_phase_peel — py -3.11 examples/poc_pxrd_phase_peel.py

Ops the type connects to (they accept signal as input)

data_to_pixel · plot_series

Same category (plot)

axes_transform · data_to_pixel · axes_frame · grid_lines · ticks · plot_series

*Provenance: annotate.py — ANNOTATE operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.