1 files changed, 24 insertions, 10 deletions
diff --git a/python/pyspark/mllib/linalg.py b/python/pyspark/mllib/linalg.py
index 2766842720..db39ed0acd 100644
--- a/python/pyspark/mllib/linalg.py
+++ b/python/pyspark/mllib/linalg.py
@@ -43,11 +43,11 @@ class SparseVector(object):
                or two sorted lists containing indices and values.
 
         >>> print SparseVector(4, {1: 1.0, 3: 5.5})
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         >>> print SparseVector(4, [(1, 1.0), (3, 5.5)])
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         >>> print SparseVector(4, [1, 3], [1.0, 5.5])
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         """
         self.size = int(size)
         assert 1 <= len(args) <= 2, "must pass either 2 or 3 arguments"
@@ -160,10 +160,9 @@ class SparseVector(object):
             return result
 
     def __str__(self):
-        inds = self.indices
-        vals = self.values
-        entries = ", ".join(["{0}: {1}".format(inds[i], vals[i]) for i in xrange(len(inds))])
-        return "[" + entries + "]"
+        inds = "[" + ",".join([str(i) for i in self.indices]) + "]"
+        vals = "[" + ",".join([str(v) for v in self.values]) + "]"
+        return "(" + ",".join((str(self.size), inds, vals)) + ")"
 
     def __repr__(self):
         inds = self.indices
@@ -213,11 +212,11 @@ class Vectors(object):
                      or two sorted lists containing indices and values.
 
         >>> print Vectors.sparse(4, {1: 1.0, 3: 5.5})
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         >>> print Vectors.sparse(4, [(1, 1.0), (3, 5.5)])
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         >>> print Vectors.sparse(4, [1, 3], [1.0, 5.5])
-        [1: 1.0, 3: 5.5]
+        (4,[1,3],[1.0,5.5])
         """
         return SparseVector(size, *args)
 
@@ -232,6 +231,21 @@ class Vectors(object):
         """
         return array(elements, dtype=float64)
 
+    @staticmethod
+    def stringify(vector):
+        """
+        Converts a vector into a string, which can be recognized by
+        Vectors.parse().
+
+        >>> Vectors.stringify(Vectors.sparse(2, [1], [1.0]))
+        '(2,[1],[1.0])'
+        >>> Vectors.stringify(Vectors.dense([0.0, 1.0]))
+        '[0.0,1.0]'
+        """
+        if type(vector) == SparseVector:
+            return str(vector)
+        else:
+            return "[" + ",".join([str(v) for v in vector]) + "]"
 
 def _test():
     import doctest