Repository: spark
Updated Branches:
  refs/heads/master 0f1f31d3a -> 354f8f11b


[SPARK-15096][ML] LogisticRegression MultiClassSummarizer numClasses can fail 
if no valid labels are found

## What changes were proposed in this pull request?

(Please fill in changes proposed in this fix)
Throw better exception when numClasses is empty and empty.max is thrown.

## How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, 
manual tests)
Add a new unit test, which calls histogram with empty numClasses.

Author: [email protected] <[email protected]>

Closes #12969 from wangmiao1981/logisticR.


Project: http://git-wip-us.apache.org/repos/asf/spark/repo
Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/354f8f11
Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/354f8f11
Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/354f8f11

Branch: refs/heads/master
Commit: 354f8f11bd4b20fa99bd67a98da3525fd3d75c81
Parents: 0f1f31d
Author: [email protected] <[email protected]>
Authored: Sat May 14 09:45:56 2016 +0100
Committer: Sean Owen <[email protected]>
Committed: Sat May 14 09:45:56 2016 +0100

----------------------------------------------------------------------
 .../org/apache/spark/ml/classification/LogisticRegression.scala  | 2 +-
 .../apache/spark/ml/classification/LogisticRegressionSuite.scala | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/spark/blob/354f8f11/mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
----------------------------------------------------------------------
diff --git 
a/mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
 
b/mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
index 3e8040d..ffd03e5 100644
--- 
a/mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
+++ 
b/mllib/src/main/scala/org/apache/spark/ml/classification/LogisticRegression.scala
@@ -745,7 +745,7 @@ private[classification] class MultiClassSummarizer extends 
Serializable {
   def countInvalid: Long = totalInvalidCnt
 
   /** @return The number of distinct labels in the input dataset. */
-  def numClasses: Int = distinctMap.keySet.max + 1
+  def numClasses: Int = if (distinctMap.isEmpty) 0 else distinctMap.keySet.max 
+ 1
 
   /** @return The weightSum of each label in the input dataset. */
   def histogram: Array[Double] = {

http://git-wip-us.apache.org/repos/asf/spark/blob/354f8f11/mllib/src/test/scala/org/apache/spark/ml/classification/LogisticRegressionSuite.scala
----------------------------------------------------------------------
diff --git 
a/mllib/src/test/scala/org/apache/spark/ml/classification/LogisticRegressionSuite.scala
 
b/mllib/src/test/scala/org/apache/spark/ml/classification/LogisticRegressionSuite.scala
index f127aa2..69650eb 100644
--- 
a/mllib/src/test/scala/org/apache/spark/ml/classification/LogisticRegressionSuite.scala
+++ 
b/mllib/src/test/scala/org/apache/spark/ml/classification/LogisticRegressionSuite.scala
@@ -256,6 +256,10 @@ class LogisticRegressionSuite
     assert(summarizer4.countInvalid === 2)
     assert(summarizer4.numClasses === 4)
 
+    val summarizer5 = new MultiClassSummarizer
+    assert(summarizer5.histogram.isEmpty)
+    assert(summarizer5.numClasses === 0)
+
     // small map merges large one
     val summarizerA = summarizer1.merge(summarizer2)
     assert(summarizerA.hashCode() === summarizer2.hashCode())


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

Reply via email to