matrix_to_angle — REPRCONV algebra op

Data kinds: matrixangle

Call: import reprconv; reprconv.matrix_to_angle(matrix) (or opsreprconv.get("matrix_to_angle"))

Usage

A rotation matrix about the z-axis → the angle [deg]. The inverse of :func:angle_to_matrix.

> The detailed description below is the original text — the summary and the headings are translated.

`atan2(R[2,1], R[1,1])` を度で返す(-180, 180]。往復は

(-180, 180] の範囲で bit 一致に近い(実測 max|Δ| = 2.8e-14 度)。

Args:

matrix: (3, 3)。

Returns:

float(度)。

Raises:

ValueError: (3,3) でない / 非有限。

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)

representation_roundtrippy -3.11 examples/representation_roundtrip.py

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

angle_to_matrix

Same category (algebra)

angle_to_matrix · rot_scale_to_matrix · matrix_to_rot_scale · shift_to_vector · vector_to_shift · cscalar_to_polar · polar_to_cscalar · countrate_to_counts


*Provenance: reprconv.py — REPRCONV 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.