From 25e50a484624096ef8e99b1e23f047706e07f6cc Mon Sep 17 00:00:00 2001
From: leios <jrs.schloss@gmail.com>
Date: Thu, 30 Apr 2020 07:26:38 +0900
Subject: [PATCH] merging with master and fixing let statements
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Co-authored-by: Juan Antonio Hernández Cánovas <juanantoniohernandezcanovas@gmail.com>
---
 .../code/javascript/thomas.js                 | 31 +++++++++++++++++++
 contents/thomas_algorithm/thomas_algorithm.md |  2 ++
 2 files changed, 33 insertions(+)
 create mode 100644 contents/thomas_algorithm/code/javascript/thomas.js

diff --git a/contents/thomas_algorithm/code/javascript/thomas.js b/contents/thomas_algorithm/code/javascript/thomas.js
new file mode 100644
index 000000000..f9aa1da9a
--- /dev/null
+++ b/contents/thomas_algorithm/code/javascript/thomas.js
@@ -0,0 +1,31 @@
+function thomas(a, b, c, x) {
+	const y = [];
+
+	y[0] = c[0] / b[0];
+	x[0] = x[0] / b[0];
+
+	for (let i = 1; i < a.length; i++) {
+		const scale = 1.0 / (b[i] - a[i] * y[i - 1]);
+		y[i] = c[i] * scale;
+		x[i] = (x[i] - a[i] * x[i - 1]) * scale;
+	}
+
+	for (let i = a.length - 2; i >= 0; i--)
+		x[i] -= y[i] * x[i + 1];
+}
+
+let a = [0.0, 2.0, 3.0];
+let b = [1.0, 3.0, 6.0];
+let c = [4.0, 5.0, 0.0];
+let x = [7.0, 5.0, 3.0];
+
+console.log("The system,");
+console.log("[1.0  4.0  0.0][x] = [7.0]");
+console.log("[2.0  3.0  5.0][y] = [5.0]");
+console.log("[0.0  3.0  6.0][z] = [3.0]");
+console.log("has the solution:\n");
+
+thomas(a, b, c, x);
+
+for (let i = 0; i < 3; i++)
+	console.log("[" + x[i] + "]");
diff --git a/contents/thomas_algorithm/thomas_algorithm.md b/contents/thomas_algorithm/thomas_algorithm.md
index 2b73868e1..70a4c682e 100644
--- a/contents/thomas_algorithm/thomas_algorithm.md
+++ b/contents/thomas_algorithm/thomas_algorithm.md
@@ -131,6 +131,8 @@ You will find this algorithm implemented [in this project](https://scratch.mit.e
 [import, lang:"kotlin"](code/kotlin/thomas.kt)
 {% sample lang="ruby" %}
 [import, lang="ruby"](code/ruby/thomas.rb)
+{% sample lang="js" %}
+[import, lang:"javascript"](code/javascript/thomas.js)
 {% endmethod %}
 
 <script>