# SciPy 1.9.1 Release Notes

SciPy 1.9.1 is a bug-fix release with no new features compared to 1.9.0. Notably, some important meson build fixes are included.

## Authors

- Anirudh Dagar (1)

- Ralf Gommers (12)

- Matt Haberland (2)

- Andrew Nelson (1)

- Tyler Reddy (14)

- Atsushi Sakai (1)

- Eli Schwartz (1)

- Warren Weckesser (2)

A total of 8 people contributed to this release. People with a “+” by their names contributed a patch for the first time. This list of names is automatically generated, and may not be fully complete.

### Issues closed for 1.9.1

- #14517: scipy/linalg/tests/test_decomp.py::TestSchur::test_sort test…

- #16765: DOC: `scipy.stats.skew` no longer returns 0 on constant input

- #16787: BUG: Can’t build 1.10 with mingw-w64 toolchain and numpy 1.21.6…

- #16813: BUG: scipy.interpolate interp1d extrapolate behaviour change…

- #16878: BUG: optimize.milp fails to execute when given exactly 3 constraints

### Pull requests for 1.9.1

- #16709: BLD: make the way we count commits for version numbering more…

- #16736: REL: prep for SciPy 1.9.1

- #16749: BLD: install missing `.pxd` files, and update TODOs/FIXMEs…

- #16750: BLD: make OpenBLAS detection work with CMake

- #16755: TST: sparse.linalg: Loosen tolerance for the lobpcg test ‘test_tolerance_float32’

- #16760: BLD: use a bit more idiomatic approach to constructing paths…

- #16768: DOC: stats.skew/kurtosis: returns NaN when input has only one…

- #16794: BLD/REL: on Windows use numpy 1.22.3 as the version to build…

- #16822: BUG/TST: linalg: Check the results of ‘schur’ more carefully.

- #16825: BUG: interpolate: fix “previous” and “next” extrapolate logic…

- #16862: BUG, DOC: Fix sphinx autosummary generation for `odr` and `czt`

- #16881: MAINT: optimize.milp: fix input validation when three constraints…

- #16901: MAINT: 1.9.1 backports

- #16904: BLD: update dependency ranges for meson-python and pybind11 for…