Repository: spark Updated Branches: refs/heads/master 2dc048081 -> bcbe44440
[MINOR] Use <= for clarity in Pi examples' Monte Carlo process ## What changes were proposed in this pull request? If my understanding is correct we should be rather looking at closed disk than the opened one. ## How was this patch tested? Run simple comparison, of the mean squared error of approaches with closed and opened disk. https://gist.github.com/mrydzy/1cf0e5c316ef9d6fbd91426b91f1969f The closed one performed slightly better, but the tested sample wasn't too big, so I rely mostly on the algorithm understanding. Author: Maria Rydzy <majrydzy...@gmail.com> Closes #15687 from mrydzy/master. Project: http://git-wip-us.apache.org/repos/asf/spark/repo Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/bcbe4444 Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/bcbe4444 Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/bcbe4444 Branch: refs/heads/master Commit: bcbe44440e6c871e217f06d2a4696fd41f1d2606 Parents: 2dc0480 Author: Maria Rydzy <majrydzy...@gmail.com> Authored: Wed Nov 2 09:09:16 2016 +0000 Committer: Sean Owen <so...@cloudera.com> Committed: Wed Nov 2 09:09:16 2016 +0000 ---------------------------------------------------------------------- examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java | 2 +- examples/src/main/python/pi.py | 2 +- examples/src/main/scala/org/apache/spark/examples/LocalPi.scala | 2 +- examples/src/main/scala/org/apache/spark/examples/SparkPi.scala | 2 +- 4 files changed, 4 insertions(+), 4 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/spark/blob/bcbe4444/examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java ---------------------------------------------------------------------- diff --git a/examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java b/examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java index 7df145e..89855e8 100644 --- a/examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java +++ b/examples/src/main/java/org/apache/spark/examples/JavaSparkPi.java @@ -54,7 +54,7 @@ public final class JavaSparkPi { public Integer call(Integer integer) { double x = Math.random() * 2 - 1; double y = Math.random() * 2 - 1; - return (x * x + y * y < 1) ? 1 : 0; + return (x * x + y * y <= 1) ? 1 : 0; } }).reduce(new Function2<Integer, Integer, Integer>() { @Override http://git-wip-us.apache.org/repos/asf/spark/blob/bcbe4444/examples/src/main/python/pi.py ---------------------------------------------------------------------- diff --git a/examples/src/main/python/pi.py b/examples/src/main/python/pi.py index e3f0c4a..37029b7 100755 --- a/examples/src/main/python/pi.py +++ b/examples/src/main/python/pi.py @@ -38,7 +38,7 @@ if __name__ == "__main__": def f(_): x = random() * 2 - 1 y = random() * 2 - 1 - return 1 if x ** 2 + y ** 2 < 1 else 0 + return 1 if x ** 2 + y ** 2 <= 1 else 0 count = spark.sparkContext.parallelize(range(1, n + 1), partitions).map(f).reduce(add) print("Pi is roughly %f" % (4.0 * count / n)) http://git-wip-us.apache.org/repos/asf/spark/blob/bcbe4444/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala ---------------------------------------------------------------------- diff --git a/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala b/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala index 720d92f..121b768 100644 --- a/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala +++ b/examples/src/main/scala/org/apache/spark/examples/LocalPi.scala @@ -26,7 +26,7 @@ object LocalPi { for (i <- 1 to 100000) { val x = random * 2 - 1 val y = random * 2 - 1 - if (x*x + y*y < 1) count += 1 + if (x*x + y*y <= 1) count += 1 } println("Pi is roughly " + 4 * count / 100000.0) } http://git-wip-us.apache.org/repos/asf/spark/blob/bcbe4444/examples/src/main/scala/org/apache/spark/examples/SparkPi.scala ---------------------------------------------------------------------- diff --git a/examples/src/main/scala/org/apache/spark/examples/SparkPi.scala b/examples/src/main/scala/org/apache/spark/examples/SparkPi.scala index 272c1a4..a5cacf1 100644 --- a/examples/src/main/scala/org/apache/spark/examples/SparkPi.scala +++ b/examples/src/main/scala/org/apache/spark/examples/SparkPi.scala @@ -34,7 +34,7 @@ object SparkPi { val count = spark.sparkContext.parallelize(1 until n, slices).map { i => val x = random * 2 - 1 val y = random * 2 - 1 - if (x*x + y*y < 1) 1 else 0 + if (x*x + y*y <= 1) 1 else 0 }.reduce(_ + _) println("Pi is roughly " + 4.0 * count / (n - 1)) spark.stop() --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@spark.apache.org For additional commands, e-mail: commits-h...@spark.apache.org