Initial commit of functions from github.com/btracey/optimize

We could get rid of aux.go completely, XxxConditionMet could go to
linesearch.go and resize to types.go, for example.

On Thu, Oct 16, 2014 at 9:02 AM, Brendan Tracey <notifications@github.com>
wrote:

> In aux.go:
>
> > @@ -0,0 +1,54 @@
> > +// Copyright ©2014 The gonum Authors. All rights reserved.
> > +// Use of this source code is governed by a BSD-style
> > +// license that can be found in the LICENSE file.
> > +
> > +package opt
> > +
> > +import "math"
> > +
> > +// ArmijioConditionMet returns true if the Armijio condition (aka sufficient decrease)
> > +// has been met. Under normal conditions, the following should be true, though this is not enforced:
> > +// 	- initGrad < 0
> > +//  - step > 0
> > +//  - 0 < funConst < 1
> > +func ArmijioConditionMet(currObj, initObj, initGrad, step, funConst float64) bool {
>
> Oh geez. Thanks. Do you have a suggestion difference than "aux" for the
> filename? Apparently it's not allowed on Windows.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/gonum/opt/pull/1/files#r18931656>.
>