[SciPy-Dev] QR decomposition with pivoting (rank revealing QR factorization)

[Martin Teichmann]

Hi List,
Hi Collin,

coincidentally, I've been working on the same problem,
and so I also want to share my two cents:

> I have added a boolean keyword argument called 'pivoted' which causes
> qr() to perform QR decomposition with pivoting (rank revealing QR

I would prefer the keyword "pivoting", since this is how it is usually
called.

> factorization). Ultimately, 'mode' should probably be used to flag
> whether or not this sort of decomposition should be done,

I think a keyword is a much better choice. Mode decides whether
the second step of finding Q is done or not, which, in principle,
has nothing to do with pivoting or not.

On the other hand, I opt for a new mode, which I would call "reflectors",
which returns the reflectors of Q calculated in the first step of
the factorization, some people out there (me) need that result.

Greetings

Martin