Is this something people would find useful? How would you like to sparsify the matrix? Using a threshold, or something else like target number of elements per row?
On Dec 2, 2011, at 10:04 AM, Ted Dunning <[email protected]> wrote: > No. > > On Fri, Dec 2, 2011 at 4:03 AM, Dan Brickley (Commented) (JIRA) < > [email protected]> wrote: > >> >> [ >> https://issues.apache.org/jira/browse/MAHOUT-880?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13161562#comment-13161562] >> >> Dan Brickley commented on MAHOUT-880: >> ------------------------------------- >> >> Does Mahout yet have a method to take a large full matrix, and convert it >> sparse matrix format (losing zero values or perhaps if it makes sense, >> near-zero values also...)? >> >>> Add some matrix method(like addition, subtraction, norm ... etc) to >> DistributedRowMatrix >>> >> ---------------------------------------------------------------------------------------- >>> >>> Key: MAHOUT-880 >>> URL: https://issues.apache.org/jira/browse/MAHOUT-880 >>> Project: Mahout >>> Issue Type: New Feature >>> Components: Math >>> Affects Versions: 0.6 >>> Reporter: Wangda Tan >>> Priority: Minor >>> Labels: DistributedRowMatrix >>> Attachments: MAHOUT-880.patch >>> >>> >>> I'm a new to Mahout, I didn't find some basic matrix functions. This >> make users cannot do many tasks by CLI or API, if user get some result >> through existing map-reduce matrix operation (like svd), he cannot do >> farther steps. I make a list for it: >>> 1) Addition, Subtraction >>> 2) Norm (like norm-1, norm-2, norm-frobenius) >>> 3) Matrix compare >>> 4) Get lower triangle, upper triangle and diagonal >>> 5) Get identity and zero matrix >>> 6) Put two or matrix to together: A = [A1, A2] >>> 7) More linear equations solver method, like Gaussian elimination (maybe >> it's hard to implement) >>> 8) import and export CSV, ARFF ... (this will very useful when user want >> to reuse result from or to other applications like MATLAB) >>> I want to know is there any plan to do this, if so, I can make some >> efforts to implement these. >> >> -- >> This message is automatically generated by JIRA. >> If you think it was sent incorrectly, please contact your JIRA >> administrators: >> https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa >> For more information on JIRA, see: http://www.atlassian.com/software/jira >> >> >>
