I'm learning about machine-learning in general and both courses I've taken
are basically intros to Python's sci-kit which is good for a high-level
look but gives no clue to the underlying algos.

I searched the J wiki for "quadratic" and found a mention from a 2005
NYCJUG meeting where we were lamenting that other environments simply have
quadratic solvers available but J does not.  Looking into it more, I was
unsure "quadratic" means in "quadratic solver"; from "Numerical Recipes", I
gather that it may refer to quadratic convergence.  On further reflection,
I'm not exactly sure what this means either but suspect it means something
like O(sqrt(n)) solution time but am not sure.  I'm also unclear if this
non-linear solver in J - http://code.jsoftware.com/wiki/Scripts/nlls - is
an example of a quadratic solver (with this follow-up page I put together -
http://code.jsoftware.com/wiki/NYCJUG/2010-11-09/Levenberg-MarquardtAlgorithm
).

Perhaps someone more acquainted with this domain can shed some light.

My ultimate goal for these sort of tools is to do something with the
million or so photos I have but I'm seeing from what I've learned so far
that the real work is in feature-extraction, so that at least is something
where I can use J to good effect.

I'm less interested in a wrapper such as the one Scott Locklin mentioned
and more interested in expressing the algorithm in an understandable,
compact form but may end up surrendering to the popularity contest and
simply using the Python library.



On Sat, Dec 2, 2017 at 6:59 PM, 'Jon Hough' via Programming <
[email protected]> wrote:

> I was looking for an svm implementation in J a while ago. To create one
> you first need a quadratic programming solver. I asked in the J forums, and
> it seems nobody has written one in J, at least publicly.
> Without a QP solver, the only other option is to try to use cvxopt or some
> similar library.
>
>
>
> On Dec 3, 2017, 6:59 AM, at 6:59 AM, devonmcc <[email protected]> wrote:
> >Does anyone have J code to implement support vector machines that they
> >would like to share?
> >
> >
> >Sent from my Verizon, Samsung Galaxy smartphone
> >----------------------------------------------------------------------
> >For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>



-- 

Devon McCormick, CFA

Quantitative Consultant
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm

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