Version 1.8.0

Features

• Python 3.15 wheels, including free-threading and Pyodide, by @henryiii in #1163
• Support flow=False in histogram projections by @Rishabh-git10 in #1109
• Add Histogram.allclose for approximate histogram comparison by @gohil-jay in #778
• Add a pytest plugin with rich assertion reporting for histogram comparisons by @gohil-jay in #763

Changes

• Support subtraction for the MultiCell storage by @henryiii in #1131
• Support vectorized NumPy-array indexing for getting and setting bins by @henryiii in #1134
• Support addition for Mean/WeightedMean views by @henryiii in #1137
• Add reflected __rsub__ and __rtruediv__ operators by @henryiii in #1155
• Accept a scalar sample argument in fill by @henryiii in #1124
• Rebin with groups: MultiCell support, flow handling, and a group_mapping protocol by @henryiii in #1148

Fixes

• Reject arithmetic with mismatched storages by @divyanshu-iitian in #1166
• Return a zero-filled vector from MultiCell sum() over zero bins instead of an empty list by @henryiii in #1132
• Raise TypeError instead of ValueError for a non-integer locator offset and a string sample= by @henryiii in #1163
• Clear error for unsupported histogram in-place operations by @henryiii in #1130
• Support common transformed axes in the numpy shortcuts by @henryiii in #1122
• Correct Mean storage string rejection and __setitem__ error message by @henryiii in #1117
• Several fixes from automated review by @henryiii in #1116 and #1118
• Promote integer storages to double on division by @henryiii in #1138
• Do not mutate input edges and validate histogramdd dimensions in the numpy module by @henryiii in #1144
• Fix out= handling, scalar division, and broadcasting in structured views by @henryiii in #1146
• Fix non-contiguous array handling and memory safety in the C++ bindings by @henryiii in #1147
• Fix indexing, __setitem__ flow transfer, and fill edge cases by @henryiii in #1149
• Avoid Boost indexed-range UB in rank-0 sum()/empty() by @henryiii in #1153
• Normalize negative integer slice bounds in indexing by @henryiii in #1156
• Remove ODR-violating operator<< for accumulators::sum by @henryiii in #1161

Performance

• Avoid deep copies in comparisons and hot paths by @henryiii in #1150

Documentation

• Cleanup, modernization, and gap-filling in the user guide by @henryiii in #1141
• Note that fancy indexing on views returns a copy by @henryiii in #1136
• Correct the wheel table and add a version-support checklist by @henryiii in #1168

Tests

• Use pytest.approx instead of NumPy assertion helpers by @gohil-jay in #780
• Validate UHI serialization against the uhi JSON schema by @henryiii in #1140
• Broaden MultiCell storage coverage by @henryiii in #1127
• Add regression test for scalar-broadcast fill on non-inclusive axes by @henryiii in #1125
• Add ND projection test for flow=False by @Rishabh-git10 in #1111
• Disable cloudpickle tests on PyPy by @henryiii in #1120
• Skip the pytest plugin end-to-end test on Emscripten by @henryiii in #1152

Internal

• Bump to Boost 1.91 by @henryiii in #1112
• Bump setup-uv to the maintained tag scheme by @henryiii in #1110
• Update cibuildwheel to v4.0 by @henryiii in #1119
• Update AGENTS instructions and ignore the CLAUDE symlink by @henryiii in #1121
• Make the nox hist session fail on a missing dir and mypy override errors by @henryiii in #1135
• Set up uv cache keys by @henryiii in #1142
• pybind11 v3 pin, MSVC /WX, config and stub cleanups by @henryiii in #1145
• Remove dead code and minor C++ cleanups by @henryiii in #1151
• Remove the needs-changelog labeler by @henryiii in #1164

New Contributors

• @Rishabh-git10 made their first contribution in #1109
• @divyanshu-iitian made their first contribution in #1166

Full Changelog: v1.7.2...v1.8.0