016ReviewmidPython / Astropy真实来源改编 Astropy

Astropy：修复嵌套 CompoundModel 的 separability 矩阵

审查一个 Astropy modeling PR：作者调整了组合模型右侧 block 的填充方式，并补了一个嵌套模型测试。

diff --git a/astropy/modeling/separable.py b/astropy/modeling/separable.py@@-        cright[-right.shape[0]:, -right.shape[1]:] = right+        # Mark every output of the nested right model as depending on its inputs.+        cright[-right.shape[0]:, -right.shape[1]:] = 1@@+def test_nested_model_shape():+    cm = m.Pix2Sky_TAN() & (m.Linear1D(10) & m.Linear1D(5))+    matrix = separability_matrix(cm)+    assert matrix.shape == (4, 4)

PR 说明codegen-agent · CI passed

Handle nested right-hand models when building separability matrices

separability_matrix can produce confusing results when a compound model contains another compound model on the right-hand side. The current block assembly assumes the right operand can always be copied directly, but nested models need every output row to be connected to their inputs in the combined coordinate matrix.

This PR marks the nested right-hand block as dependent on its input columns by filling the target block with 1s. This keeps the combined matrix shape correct and avoids losing the nested model in the parent composition.

Added a nested model regression test using Pix2Sky_TAN with two Linear1D components to verify the combined separability matrix has the expected dimensions. Existing modeling tests pass.

背景3 条

Astropy separability_matrix returns a boolean matrix describing which model outputs depend on which inputs.

CompoundModel assembly builds a block matrix from left and right operand matrices. A nested operand may already have meaningful internal separability structure.

The review context includes the pre-patch block assembly excerpt in src-separable.py.