diff --git a/mllib/src/main/scala/org/apache/spark/mllib/clustering/PIClustering.scala b/mllib/src/main/scala/org/apache/spark/mllib/clustering/PIClustering.scala
index d480dad72373e..d0724b4d42534 100644
--- a/mllib/src/main/scala/org/apache/spark/mllib/clustering/PIClustering.scala
+++ b/mllib/src/main/scala/org/apache/spark/mllib/clustering/PIClustering.scala
@@ -204,7 +204,7 @@ Updating vertex[2] from 0.2777777777777778 to 0.29803684040501227
 
   def gaussianDist(c1arr: DVector, c2arr: DVector, sigma: Double) = {
     val c1c2 = c1arr.zip(c2arr)
-    val dist = Math.exp((0.5 / Math.pow(sigma, 2.0)) * c1c2.foldLeft(0.0) {
+    val dist = Math.exp((-0.5 / Math.pow(sigma, 2.0)) * c1c2.foldLeft(0.0) {
       case (dist: Double, (c1: Double, c2: Double)) =>
         dist + Math.pow(c1 - c2, 2)
     })
@@ -246,12 +246,15 @@ Updating vertex[2] from 0.2777777777777778 to 0.29803684040501227
         (ix, vect)
       }
     }, nVertices)
+    println(s"Affinity:\n${LA.printMatrix(affinityRddNotNorm.collect.map(_._2._2),
+      nVertices, nVertices)}")
     val materializedRowSums = rowSums.map{ _.value}
     val affinityRdd = affinityRddNotNorm.map { case (rowx, (vid, vect)) =>
       (vid, vect.map {
         _ / materializedRowSums(rowx)
       })
     }
+    println(s"W:\n${LA.printMatrix(affinityRdd.collect.map(_._2), nVertices, nVertices)}")
     (affinityRdd, materializedRowSums)
   }
 
diff --git a/mllib/src/test/scala/org/apache/spark/mllib/clustering/PIClusteringSuite.scala b/mllib/src/test/scala/org/apache/spark/mllib/clustering/PIClusteringSuite.scala
index 862f81ae00b7a..b79a6d8343531 100644
--- a/mllib/src/test/scala/org/apache/spark/mllib/clustering/PIClusteringSuite.scala
+++ b/mllib/src/test/scala/org/apache/spark/mllib/clustering/PIClusteringSuite.scala
@@ -125,15 +125,23 @@ class PIClusteringSuite extends FunSuite with LocalSparkContext {
   }
   def concentricCirclesTest() = {
     val sigma = 1.0
-    val nIterations = 20
+    val nIterations = 50
     val nClusters = 3
     val circleSpecs = Seq(
-      CircleSpec(Point(0.0,0.0), 0.2, .1, 4),
-      CircleSpec(Point(0.0,0.0), 1.0, .1, 8),
-      CircleSpec(Point(0.0,0.0), 2.0, .1, 16)
-//      CircleSpec(Point(0.0,0.0), 0.2, .1, 5),
+    // Best results for 30 points
+      CircleSpec(Point(0.0,0.0), 0.03, .1, 3),
+      CircleSpec(Point(0.0,0.0), 0.3, .03, 12),
+      CircleSpec(Point(0.0,0.0), 1.0, .01, 15)
+
+    // DECENT
+//      CircleSpec(Point(0.0,0.0), 0.1, .1, 5),
 //      CircleSpec(Point(0.0,0.0), 1.0, .1, 15),
-//      CircleSpec(Point(0.0,0.0), 2.0, .1, 30)
+//      CircleSpec(Point(0.0,0.0), 2.5, .1, 30)
+
+    // GOOD but big (90 points)
+//      CircleSpec(Point(0.0,0.0), 0.1, .1, 5),
+//      CircleSpec(Point(0.0,0.0), 1.0, .03, 25),
+//      CircleSpec(Point(0.0,0.0), 2.5, .01, 60)
     )
     withSpark { sc =>
       val vertices = createConcentricCirclesData(circleSpecs).zipWithIndex.map { case (p, ix) =>
@@ -174,8 +182,10 @@ object PIClusteringSuite {
   val LA = PICLinalg
   val A = Array
 
+  def pdoub(d: Double) = f"$d%1.6f"
+
   case class Point(x: Double, y: Double) {
-    override def toString() = s"($x,$y)"
+    override def toString() = s"(${pdoub(x)},${pdoub(y)})"
   }
   case class CircleSpec(center: Point, radius: Double, noiseToRadiusRatio: Double,
                         nPoints: Int, uniformDistOnCircle: Boolean = true)
@@ -192,13 +202,13 @@ object PIClusteringSuite {
       circlePoints
     }
     val points = circles.flatten
-    printPoints(points)
+    println(printPoints(points))
     points
   }
 
   def printPoints(points: Seq[Point]) = {
     val sorted = points.sortWith { case (p1, p2) =>
-      if (p1.y == p2.y) {
+      if (LA.withinTol(p1.y-p2.y)) {
         p1.x <= p2.x
       } else {
         p1.y >= p2.y