mit-ocw

commit b2a4f54514156be7f3690a300b43ee16c50b3431
parent 01eed5d2f3647f3e465891f36c9741c6c24064b7
Author: Andrew Laack <andrew@laack.co>
Date:   Wed, 13 May 2026 02:13:17 -0500

Implemented in go and python

Diffstat:
A
6.172-perf-engineering/mat-mul/mat_mul.go
 | 
55
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
A
6.172-perf-engineering/mat-mul/mat_mul.py
 | 
30
++++++++++++++++++++++++++++++

2 files changed, 85 insertions(+), 0 deletions(-)
diff --git a/6.172-perf-engineering/mat-mul/mat_mul.go b/6.172-perf-engineering/mat-mul/mat_mul.go
@@ -0,0 +1,55 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"time"
+)
+
+const n = 400
+
+func randInit(arr [n][n]float32) [n][n]float32 {
+
+	for i := range len(arr) {
+		for j := range len(arr[i]) {
+			arr[i][j] = rand.Float32()
+		}
+	}
+
+	return arr
+
+}
+
+func main(){
+
+
+	A := [n][n]float32{}
+	B := [n][n]float32{}
+	C := [n][n]float32{}
+
+
+	A = randInit(A)
+	B = randInit(B)
+
+	start := time.Now()
+
+	for i := range A {
+		for k := range B {
+			for j := range B {
+				C[i][j] += A[i][k] * B[k][j]
+			}
+		}
+	}
+
+	end := time.Now()
+
+	fmt.Println(end.Sub(start).Seconds())
+}
+
+// This runs in:
+
+// 1: 0.048146089
+// 2: 0.047572412
+// 3: 0.047875806
+
+// AVG: 0.047864769
diff --git a/6.172-perf-engineering/mat-mul/mat_mul.py b/6.172-perf-engineering/mat-mul/mat_mul.py
@@ -0,0 +1,30 @@
+import random
+import time
+
+n = 400
+
+A = [[random.random() for _ in range(n)] for _ in range(n)]
+B = [[random.random() for _ in range(n)] for _ in range(n)]
+
+C = [[0 for _ in range(n)] for _ in range(n)]
+
+
+start = time.time()
+
+for i in range(len(A)):
+    for k in range(len(B)):
+        for j in range(len(B)):
+            C[i][j] += A[i][k] * B[k][j]
+
+
+end = time.time()
+
+print(end - start)
+
+# This runs in:
+
+# 1: 13.906554698944092
+# 2: 13.789746761322021
+# 3: 14.16126012802124
+
+# AVG: 13.952520529429117