Labels are certainly valuable (esp. for text) and if they are somehow built into the matrix lib, it will make the user's life easier. I share similar concerns w/ Ted and think his idea for a LabelWrapper class is a great idea.
Jason On Sun, Mar 16, 2008 at 5:28 PM, Ted Dunning <[EMAIL PROTECTED]> wrote: > > I have been batting that question back and forth in my own head recently. > > It IS absolutely a huge help to have labels. R has the data.frame to do > this and it helps enormously. I have done it in some applications and it > saved endless hassle. > > On the other hand, there is a real danger that the label functionality > would > get sucked into a single implementation. Labels really are an orthogonal > concern that are (should be) independent of how the matrix is implemented. > > So should there really be something like a LabeledMatrix wrapper that > provides this labeling service to any matrix? > > > On 3/16/08 2:23 PM, "Grant Ingersoll (JIRA)" <[EMAIL PROTECTED]> wrote: > > > > > [ > > > https://issues.apache.org/jira/browse/MAHOUT-6?page=com.atlassian.jira.plugin > . > > > system.issuetabpanels:comment-tabpanel&focusedCommentId=12579261#action_125792 > > 61 ] > > > > Grant Ingersoll commented on MAHOUT-6: > > -------------------------------------- > > > > Does it make sense to be able to assign labels to the rows and columns > and > > maybe even have it accessible as a map? For instance, I think I could > use > > these for the bayesian classifier implementation I am working on and it > would > > make sense to be able to label the features and the labels. Naturally, > I can > > store the information elsewhere as well, but didn't know whether it made > sense > > to keep the info w/ the matrix. > > > >> Need a matrix implementation > >> ---------------------------- > >> > >> Key: MAHOUT-6 > >> URL: https://issues.apache.org/jira/browse/MAHOUT-6 > >> Project: Mahout > >> Issue Type: New Feature > >> Reporter: Ted Dunning > >> Assignee: Grant Ingersoll > >> Attachments: MAHOUT-6a.diff, MAHOUT-6b.diff, MAHOUT-6c.diff, > >> MAHOUT-6d.diff, MAHOUT-6e.diff, MAHOUT-6f.diff, MAHOUT-6g.diff, > >> MAHOUT-6h.patch, MAHOUT-6i.diff, MAHOUT-6j.diff, MAHOUT-6k.diff, > >> MAHOUT-6l.patch > >> > >> > >> We need matrices for Mahout. > >> An initial set of basic requirements includes: > >> a) sparse and dense support are required > >> b) row and column labels are important > >> c) serialization for hadoop use is required > >> d) reasonable floating point performance is required, but awesome FP is > not > >> e) the API should be simple enough to understand > >> f) it should be easy to carve out sub-matrices for sending to different > >> reducers > >> g) a reasonable set of matrix operations should be supported, these > should > >> eventually include: > >> simple matrix-matrix and matrix-vector and matrix-scalar linear > algebra > >> operations, A B, A + B, A v, A + x, v + x, u + v, dot(u, v) > >> row and column sums > >> generalized level 2 and 3 BLAS primitives, alpha A B + beta C and A > u + > >> beta v > >> h) easy and efficient iteration constructs, especially for sparse > matrices > >> i) easy to extend with new implementations > > -- Jason Rennie Head of Machine Learning Technologies, StyleFeeder http://www.stylefeeder.com/ Samantha's blog & pictures: http://samanthalyrarennie.blogspot.com/
