2) OK

Now I know where tiny abs(x)*sqrt($macheps) for x's 

near zero are better: x^alpha, alpha<1

Now I can use such way around:

use quality 1 for powers<1 near zero

and quality 2 for the rest

Oleh

P.S. I was surprised to see such

established thing as  Minpack

does the way it does.

I think,  the legacy code must

contain something better.

Of course, the problem is

closed for the time being. 

On Wed, 30 Dec 2015, oleg_komashko@ukr.net wrote:

> Attached

Our "quality 0" is the standard Minpack code, I don't think we want 
to mess with it. (But we may decide it shouldn't be the default.)

Allin