Github user dusenberrymw commented on a diff in the pull request:

    https://github.com/apache/spark/pull/7554#discussion_r35827501
  
    --- Diff: python/pyspark/mllib/linalg.py ---
    @@ -1152,9 +1156,385 @@ def sparse(numRows, numCols, colPtrs, rowIndices, 
values):
             return SparseMatrix(numRows, numCols, colPtrs, rowIndices, values)
     
     
    +class DistributedMatrix(object):
    +    """
    +    Represents a distributively stored matrix backed by one or
    +    more RDDs.
    +
    +    """
    +    def numRows(self):
    +        """Get or compute the number of rows."""
    +        raise NotImplementedError
    +
    +    def numCols(self):
    +        """Get or compute the number of cols."""
    +        raise NotImplementedError
    +
    +
    +class RowMatrix(DistributedMatrix):
    +    """
    +    Represents a row-oriented distributed Matrix with no meaningful
    +    row indices.
    +
    +    .. note:: Experimental
    +    """
    +    def __init__(self, rows, numRows=0, numCols=0):
    +        """
    +        Create a wrapper over a Java RowMatrix.
    +
    +        :param rows: An RDD of Vectors.
    +        """
    +        if not isinstance(rows, RDD):
    +            raise TypeError("rows should be an RDD object, got %s" % 
type(rows))
    +        first = rows.first()
    +        if not isinstance(first, Vector):
    +            raise TypeError("rows should be an RDD of Vectors, got an RDD 
of %s" % type(first))
    +
    +        javaRowMatrix = callMLlibFunc("createRowMatrix", rows, 
long(numRows), int(numCols))
    +        self._jrm = JavaModelWrapper(javaRowMatrix)
    +        self.rows = rows
    +
    +    @staticmethod
    +    def _from_java(javaRowMatrix):
    --- End diff --
    
    Yeah I agree, it's not ideal, but it does keep the API clean.  An 
alternative would be to add an optional Java model parameter to each of the 
class constructors, and use it if present.  Then we could just construct the 
Java model on the Scala/Java side, grab it's rows, and pass both of those into 
the class constructors, bypassing the final step of reconstruction.  This 
parameter wouldn't be very useful for the end user though.
    
    @mengxr Do you have any thoughts on this?


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to