NEWS

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pycnogrid 0.2.1

• Changed the default cell_allocation from "area" to "centroid". Centroid allocation preserves represented source-zone totals because each target cell is assigned to one source polygon.
• Marked cell_allocation = "area" as experimental. Fractional area allocation preserves the overall represented total but may not preserve individual source-zone totals when target cells overlap multiple sources.
• Added regression tests for individual source-zone preservation, including zero-valued source zones.

pycnogrid 0.2.0 (2026-07-10)

• Added to_grid() as the main interface for pycnophylactic interpolation to multiple grid systems.
• Added support for A5, S2, ISEA, local raster and local hex grids.
• Added cell_inclusion and cell_allocation options.
• Added support for higher-order neighbourhood smoothing.
• Added package vignette and expanded examples.
• Improved tests and CRAN-readiness.

pycnogrid 0.1.0

• Initial development release.
• Added to_h3() for pycnophylactic interpolation to H3 grids.
• Added example NYC census tract datasets.
• Added unit tests and vignette infrastructure.