sweep-reference-validation: pathfinding MATCHES (scipy/skimage refs)

Claude-Session: https://claude.ai/code/session_0155N4QGamQVxgpAAPbpQNq4

Author: brendancol

.claude/sweep-reference-validation-state.csv

@@ -1,3 +1,4 @@
-module,last_inspected,issue,severity_max,verdict,tolerance,notes
-convolution,2026-07-02,3619,MEDIUM,CONVENTION-DIFF,0.0 exact (float64),scipy 1.16.1; gdal-unavailable astropy-unavailable; cuda True. convolve_2d interior MATCHES scipy.ndimage.correlate exactly (0.0) across nan/nearest/reflect/wrap; cupy parity 0.0. circle_kernel/annulus_kernel match analytic int-truncated disc exactly; calc_cellsize correct. CONVENTION-DIFF: named 'convolution' but computes cross-correlation (kernel not flipped) -> diverges from scipy.ndimage.convolve on asymmetric kernels (built-in kernels are symmetric so common path unaffected). Convention was undocumented -> MEDIUM doc fix + golden test pinning correlation.
-geotiff,2026-07-02,,,MATCHES,rtol=1e-6 float64; float32 codecs exact,"rasterio 1.4.4 (GDAL 3.10.3); gdal-cli 3.11.4; tifffile 2026.3.3; richdem-unavailable; osgeo-python-unavailable. Reader/writer round-trip vs rasterio/GDAL: codecs zstd/deflate/lzw/packbits/none + predictor 2&3 dmax=0; CRS EPSG:32611 & 4326 round-trip exact; GeoTransform north-up, non-square px, tiepoint & ModelTransformation all correct; nodata float-NaN->sentinel + int16/uint8/int32/uint16 sentinels exact; BigTIFF magic+data ok; windowed reads match rasterio.Window incl coord alignment; multiband round-trips (band-last is xrspatial's documented convention); COG valid per 'rio cogeo validate'; overview mean matches numpy block-mean to float32 ulp; tifffile tag check: Compression/Predictor/SampleFormat/GeoKeyDir all correct. Existing repo parity suite parity/test_reference.py 31 passed (incl dask+cupy). No divergence; golden_corpus already pins parity."
+module,last_inspected,issue,severity_max,verdict,tolerance,notes
+convolution,2026-07-02,3619,MEDIUM,CONVENTION-DIFF,0.0 exact (float64),scipy 1.16.1; gdal-unavailable astropy-unavailable; cuda True. convolve_2d interior MATCHES scipy.ndimage.correlate exactly (0.0) across nan/nearest/reflect/wrap; cupy parity 0.0. circle_kernel/annulus_kernel match analytic int-truncated disc exactly; calc_cellsize correct. CONVENTION-DIFF: named 'convolution' but computes cross-correlation (kernel not flipped) -> diverges from scipy.ndimage.convolve on asymmetric kernels (built-in kernels are symmetric so common path unaffected). Convention was undocumented -> MEDIUM doc fix + golden test pinning correlation.
+geotiff,2026-07-02,,,MATCHES,rtol=1e-6 float64; float32 codecs exact,"rasterio 1.4.4 (GDAL 3.10.3); gdal-cli 3.11.4; tifffile 2026.3.3; richdem-unavailable; osgeo-python-unavailable. Reader/writer round-trip vs rasterio/GDAL: codecs zstd/deflate/lzw/packbits/none + predictor 2&3 dmax=0; CRS EPSG:32611 & 4326 round-trip exact; GeoTransform north-up, non-square px, tiepoint & ModelTransformation all correct; nodata float-NaN->sentinel + int16/uint8/int32/uint16 sentinels exact; BigTIFF magic+data ok; windowed reads match rasterio.Window incl coord alignment; multiband round-trips (band-last is xrspatial's documented convention); COG valid per 'rio cogeo validate'; overview mean matches numpy block-mean to float32 ulp; tifffile tag check: Compression/Predictor/SampleFormat/GeoKeyDir all correct. Existing repo parity suite parity/test_reference.py 31 passed (incl dask+cupy). No divergence; golden_corpus already pins parity."
+pathfinding,2026-07-08,3655,,MATCHES,1e-12 rel (observed <=2e-15),"a_star_search vs scipy 1.16.1 sparse.csgraph.dijkstra + skimage 0.26.0 MCP_Geometric + analytic open-grid truth; 64x64 open/maze/friction/NaN-friction/anisotropic inputs, 4+8 conn; path chains adjacency+increment consistent; backend parity numpy/dask+numpy/cupy/dask+cupy confirmed (CUDA host); no prior golden test -> added golden-value tests (#3655); gdal/richdem/wbt not applicable to pathfinding"