Factory method, creates the extending class and returns a new instance
Write a text delimited file(s) with the row and column IDs from dictionaries.
write location, usually a directory
params to control writing
the org.apache.mahout.math.drm.DistributedContext used to do a distributed write
Adds the equivalent of blank rows to the sparse CheckpointedDrm, which only changes the row cardinality value.
number to use for new row cardinality, should be larger than current
a new IndexedDataset or extending class with new cardinality
should be done before any optimizer actions are performed on the matrix or you'll get unpredictable results.