[SPARK-16372] Retag RDD to tallSkinnyQR of RowMatrix

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0
• Component/s: MLlib
• Assignee: Xusen Yin Assign to me
• Reporter: Xusen Yin
• Created: 04/Jul/16 22:53
• Updated: 14/Jul/16 16:50
• Resolved: 07/Jul/16 10:28

Description

The following Java code because of type erasing:

JavaRDD<Vector> rows = jsc.parallelize(...);
RowMatrix mat = new RowMatrix(rows.rdd());
QRDecomposition<RowMatrix, Matrix> result = mat.tallSkinnyQR(true);

We should use retag to restore the type to prevent the following exception:

java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Lorg.apache.spark.mllib.linalg.Vector;

Issue Links

• blocks: SPARK-13015 Replace example code in mllib-data-types.md using include_example
• is related to: SPARK-11497 PySpark RowMatrix Constructor Has Type Erasure Issue
• links to: [Github] Pull Request #14051 (yinxusen)