Btw (Just to be precise), in your example of "mm" file.. the metadata is "4 3 6" but the following non-zero values are only up to row number 3. So, either it was a typo or the 4th row contains all zeros.
On Mon, Feb 15, 2016 at 4:26 PM, Shirish Tatikonda < shirish.tatiko...@gmail.com> wrote: > Both "mm" and "text" formats are identical except for a couple of > differences: > > 1) for "mm": the matrix metadata is included in the first two lines; and > for "text": the metadata is present in the associated .mtd file > 2) "mm" data must be in a single file (i.e., no *part* files) where > "text" data can span multiple *part* files (like any other file on HDFS). > > The support for "mm" is created mainly for the purpose of > importing/exporting data in the format that R likes. > > Shirish > > On Mon, Feb 15, 2016 at 4:17 PM, Deron Eriksson <deroneriks...@gmail.com> > wrote: > >> Hi, >> >> I have a question with regards to text vs mm. Isn't the mm coordinate >> format identical to the text format but the mm data file happens to >> include >> the metadata line for rows, cols, and nnzs, so shouldn't they scale the >> same since the text row values (i,j,v) correspond to the mm rows? >> >> If we have the following MM: >> %%MatrixMarket matrix coordinate real general >> 4 3 6 >> 1 1 1.0 >> 1 2 2.0 >> 1 3 3.0 >> 3 1 7.0 >> 3 2 8.0 >> 3 3 9.0 >> >> The corresponding text format (with accompanying metadata file) is: >> 1 1 1.0 >> 1 2 2.0 >> 1 3 3.0 >> 3 1 7.0 >> 3 2 8.0 >> 3 3 9.0 >> >> So aren't these formats essentially the same? >> >> Deron >> >> >> On Mon, Feb 15, 2016 at 3:56 PM, Matthias Boehm <mbo...@us.ibm.com> >> wrote: >> >> > The meta data file is still useful in order to get the format. In case >> of >> > matrix market, errors will be raised if included meta data is >> inconsistent. >> > So no, we should not disallow to specify the meta data. In general, we >> > anyway recommend using text (textcell) instead mm (matrix market) for >> > scalability reasons. >> > >> > Regards, >> > Matthias >> > >> > [image: Inactive hide details for Deron Eriksson ---02/15/2016 03:45:46 >> > PM---Hi, The Matrix Market coordinate format contains # rows, #]Deron >> > Eriksson ---02/15/2016 03:45:46 PM---Hi, The Matrix Market coordinate >> > format contains # rows, # columns, and # >> > >> > From: Deron Eriksson <deroneriks...@gmail.com> >> > To: dev@systemml.incubator.apache.org >> > Date: 02/15/2016 03:45 PM >> > Subject: Matrix Market format with metadata file >> > ------------------------------ >> > >> > >> > >> > Hi, >> > >> > The Matrix Market coordinate format contains # rows, # columns, and # >> > non-zero values as metadata near the top of a matrix data file. >> > >> > If I write a matrix in mm format using SystemML, no metadata file is >> > created since the metadata is stored within the data file. >> > >> > However, when reading a matrix with mm format, I can supply a metadata >> > file, even though metadata exists in the matrix data file. Is there any >> > reason for this, or should this be disallowed since the metadata file is >> > redundant and can cause confusion, since metadata values can then be >> > specified in two places, which then brings up the question, "which >> metadata >> > value should be used"? >> > >> > Deron >> > >> > >> > >> > >