Github user srowen commented on a diff in the pull request:
https://github.com/apache/spark/pull/22784#discussion_r228724515
--- Diff: mllib/src/main/scala/org/apache/spark/mllib/feature/PCA.scala ---
@@ -49,7 +50,16 @@ class PCA @Since("1.4.0") (@Since("1.4.0") val k: Int) {
"Try reducing the parameter k for PCA, or reduce the input feature "
+
"vector dimension to make this tractable.")
- val mat = new RowMatrix(sources)
+ val mat = if (numFeatures > 65535) {
+ val meanVector = Statistics.colStats(sources).mean
--- End diff --
Rather than call `.toArray` and `.zipped` below, can this not be written as
Vector - Vector in the loop below? might be more efficient.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
