I've opened a pull request (https://github.com/scipy/scipy/pull/6051) to increase the

minimum required LAPACK version to 3.3.1 rather than 3.1.0.

Here's some context. 3.1.0 was released on November 12, 2006. 3.3.1 was

released on April 18 2011. 3.3.1 is also the LAPACK version available by default on

the Travis CI build workers.

There are several advantages to doing this. It lets us avoid running into bugs in

older LAPACK versions (one example is

https://github.com/scipy/scipy/issues/5039). It also allows us to add a significant

number of LAPACK routines to the Cython LAPACK API. The Cython LAPACK API

consists of the routines common to all supported LAPACK versions. Increasing the

minimum requirement all the way up to 3.3.1 gives us access to most of the new

routines added between 3.1.0 and 3.3.1. A full list of the routines this adds is

available in the pull request.

The main change I expect this to make for users is that people using systems

sufficiently old to not have LAPACK 3.3.1 available through the package manager

will now have to build LAPACK from source rather than linking against the LAPACK

provided by their operating system. Given that systems that old are becoming less

common and that many people use more recent optimized implementations of

BLAS and LAPACK, I expect that this won't impact a huge number of people.

Is this a change that makes sense to everyone?

Best,

Ian Henriksen