rank_spearman — IMGMETRICS iqa op

• Data kinds: any × any → scalar

• Call: import fullseye as fs; fs.ledger.rank_spearman(x, y) -> 'float' (to call the implementation directly, import iqatid; iqatid.rank_spearman(x, y) -> 'float'; from the registry, opsimgmetrics.get("rank_spearman"))

Usage

> This operator's description has not been translated yet. The original text follows as it is.

Spearman の順位相関 ρ = 平均順位どうしの Pearson 相関(同順位があっても正しい形。古典式 1 − 6Σd²/(n(n²−1)) は

同順位が無いときだけ一致)。単調増加で 1、反転で −1。どちらかが定数なら `nan`(順位の分散が 0、相関は定義されない)。

±inf は順序だけ使う(完全一致の PSNR = inf を落とさない)。Raises `ValueError`: 長さ不一致・2 未満・nan。

Detailed usage guide

• image_difference_metrics family guide

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)

• poc_iqa_fsim_gmsd_vif — py -3.11 examples/poc_iqa_fsim_gmsd_vif.py

• poc_iqa_tid2013 — py -3.11 examples/poc_iqa_tid2013.py

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

luma_limited_u8 · rank_data · tid2013_index

Same category (iqa)

luma_limited_u8 · rank_data · rank_kendall_b · tid2013_published · tid2013_root · tid2013_index · tid2013_metric_values · tid2013_evaluate

*Provenance: iqatid.py — IMGMETRICS 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.