- The maximum thread count can now be set at import-time by setting the
environment variable 'NUMEXPR_MAX_THREADS'. The default number of
max threads was lowered from 4096 (which was deemed excessive) to 64.
- A number of imports were removed (pkg_resources) or made lazy (cpuinfo) in
order to speed load-times for downstream packages (such as `pandas`, `sympy`,
and `tables`). Import time has dropped from about 330 ms to 90 ms. Thanks to
Jason Sachs for pointing out the source of the slow-down.
- Thanks to Alvaro Lopez Ortega for updates to benchmarks to be compatible with
Python 3.
- Travis and AppVeyor now fail if the test module fails or errors.
- Thanks to Mahdi Ben Jelloul for a patch that removed a bug where constants
in `where` calls would raise a ValueError.
- Fixed a bug whereby all-constant power operations would lead to infinite
recursion.