Can you attach that to the JIRA or mail it directly to me?  The mailing list
strips attachments.

On Sun, Oct 10, 2010 at 10:18 PM, Dmitriy Lyubimov <[email protected]>wrote:

> Here you go, initial draft. It is basically done to your spec except i am
> using in-place amended gramSchmidt and correct for the number of blocks and
> make sure that at any time mapper can collect at least k+p rows for the next
> block.
>
> -d
>
>
> On Sun, Oct 10, 2010 at 10:40 AM, Ted Dunning <[email protected]>wrote:
>
>> Nice work dima!
>>
>> Can you write a paragraph showing just what your current intended
>> algorithm.  I can run a few checks in r.
>>
>> Sent from my iPhone
>>
>> On Oct 10, 2010, at 9:53 AM, "Dmitriy Lyubimov (JIRA)" <[email protected]>
>> wrote:
>>
>> >
>> >    [
>> https://issues.apache.org/jira/browse/MAHOUT-376?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12919567#action_12919567]
>> >
>> > Dmitriy Lyubimov edited comment on MAHOUT-376 at 10/10/10 12:52 PM:
>> > --------------------------------------------------------------------
>> >
>> > ok, i got to BBt normalized for rank deficiences in Q blocks.
>> >
>> > What eigensolver should i use in context of Mahout? I know there's
>> something in that Cern library but it is all deprecateed. There's also a
>> solver in apache commons, but it is not readily imported into the mahout
>> core.
>> >
>> > Thanks.
>> >
>> > PS.
>> >
>> > so i got to singular values now. I run a unit test so that k+p=n.  When
>> i parameterize algorithm so that only one Q-block is produced , the
>> eigenvalues match the stock result at least as good as 10E-5.  Which is
>> expected under the circumstances. however as soon as i increase number of
>> Q-blocks >1, the singular values go astray as much as 10%. Not good. In both
>> cases, the entire Q passes the orthonormality test. I guess it means that as
>> i thought before, doing block orthonormalization this way does result in a
>> subspace different from original span by Y.I need to research on doing
>> orthonormalization with blocks.  I think that's the only showstopper here
>> that is still left. It may result in a rewrite that splits one job producing
>> both Q and Bt, into several though.
>> >
>> >      was (Author: dlyubimov2):
>> >    ok, i got to BBt normalized for rank deficiences in Q blocks.
>> >
>> > What eigensolver should i use in context of Mahout? I know there's
>> something in that Cern library but it is all deprecateed. There's also a
>> solver in apache commons, but it is not readily imported into the mahout
>> core.
>> >
>> > Thanks.
>> >
>> > PS. i tried EigenvalueDecomposition from cern library. I know i am quite
>> likely providing an ill-conditioned matrix in my unit test but strange thing
>> is that eigen values are not always in descending order. i thought they were
>> supposed to come out in descending order?
>> >
>> >> Implement Map-reduce version of stochastic SVD
>> >> ----------------------------------------------
>> >>
>> >>                Key: MAHOUT-376
>> >>                URL: https://issues.apache.org/jira/browse/MAHOUT-376
>> >>            Project: Mahout
>> >>         Issue Type: Improvement
>> >>         Components: Math
>> >>           Reporter: Ted Dunning
>> >>           Assignee: Ted Dunning
>> >>            Fix For: 0.5
>> >>
>> >>        Attachments: MAHOUT-376.patch, sd-bib.bib, sd.pdf, sd.tex,
>> Stochastic SVD using eigensolver trick.pdf
>> >>
>> >>
>> >> See attached pdf for outline of proposed method.
>> >> All comments are welcome.
>> >
>> > --
>> > This message is automatically generated by JIRA.
>> > -
>> > You can reply to this email to add a comment to the issue online.
>> >
>>
>
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