From b5c2b349d070f9bbb703bc1e3e6bd6aa31c8779b Mon Sep 17 00:00:00 2001
From: Simon Parten <quafadas@gmail.com>
Date: Thu, 26 Sep 2024 14:12:56 +0200
Subject: [PATCH] bench

---
 benchmark/src/variance.scala | 75 ++++++++++++++++++++++++++++++++++++
 justfile                     |  2 +-
 2 files changed, 76 insertions(+), 1 deletion(-)
 create mode 100644 benchmark/src/variance.scala

diff --git a/benchmark/src/variance.scala b/benchmark/src/variance.scala
new file mode 100644
index 0000000..3f029e9
--- /dev/null
+++ b/benchmark/src/variance.scala
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2020, 2021, Ludovic Henry
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Please contact git@ludovic.dev or visit ludovic.dev if you need additional
+ * information or have any questions.
+ */
+
+package vecxt.benchmark
+
+import org.openjdk.jmh.annotations.*
+import org.openjdk.jmh.infra.Blackhole
+// import vecxt.Matrix.*
+import vecxt.BoundsCheck
+import scala.compiletime.uninitialized
+import vecxt.*
+import jdk.incubator.vector.VectorSpecies
+import jdk.incubator.vector.VectorOperators
+import jdk.incubator.vector.DoubleVector
+
+@State(Scope.Thread)
+class VarianceBenchmark extends BLASBenchmark:
+
+  @Param(Array("3", "128", "100000"))
+  var len: String = uninitialized;
+
+  var arr: Array[Double] = uninitialized
+
+  // format: off
+  @Setup(Level.Trial)
+  def setup: Unit =
+    arr = randomDoubleArray(len.toInt);    
+    ()
+  end setup
+
+  extension (vec: Array[Double])
+    inline def variance2: Double =
+      // https://www.cuemath.com/sample-variance-formula/
+      val μ = vec.mean
+      vec.map(i => (i - μ) * (i - μ)).sum / (vec.length - 1)
+  
+  
+
+  @Benchmark
+  def var_loop(bh: Blackhole) =
+    val r = arr.variance2
+    bh.consume(r);
+  end var_loop  
+
+
+  @Benchmark
+  def var_vec(bh: Blackhole) =
+    val r = arr.variance
+    bh.consume(r);
+  end var_vec
+end VarianceBenchmark
+
+
diff --git a/justfile b/justfile
index 1d65b3f..2a7548f 100644
--- a/justfile
+++ b/justfile
@@ -7,7 +7,7 @@ benchmark:
   mill benchmark.runJmh -jvmArgs --add-modules=jdk.incubator.vector -rf json
 
 benchmarkOnly:
-  mill benchmark.runJmh -jvmArgs --add-modules=jdk.incubator.vector -rf json vecxt.benchmark.LogicalBenchmark
+  mill benchmark.runJmh -jvmArgs --add-modules=jdk.incubator.vector -rf json vecxt.benchmark.VarianceBenchmark
 
 setJvm:
   eval "$(cs java --jvm 21 --env)"
\ No newline at end of file