First Commit

Matrix.js

@@ -0,0 +1,49 @@
+
+import Vector 	from "./Vector.js"
+
+function random() {
+	let seed = 12345; // fixed seed
+
+	return function() {
+		seed = ( seed * 16807 ) % 2147483647;
+		return ( seed - 1 ) / 2147483646;
+	};
+}
+
+const randomFix = random();
+
+export default class Matrix {
+	constructor( rows, cols, fillValue = 0 ) {
+		this.rows = rows;
+		this.cols = cols;
+		this.data = new Array( rows );
+		for ( let i = 0 ; i < rows ; i++ ) {
+			this.data[ i ] = new Array( cols );
+			for ( let j = 0 ; j < cols ; j++ ) {
+				this.data[ i ][ j ] = fillValue;
+			}
+		}
+	}
+
+	static random( rows, cols, scale = 0.1 ) {
+		const mat = new Matrix( rows, cols );
+		for ( let i = 0 ; i < rows ; i++ ) {
+			for ( let j = 0 ; j < cols ; j++ ) {
+				mat.data[ i ][ j ] = ( randomFix() - 0.5 ) * scale;
+			}
+		}
+		return mat;
+	}
+
+	static matVecMul( mat, vec ) {
+		const result = new Vector( mat.rows );
+		for ( let i = 0 ; i < mat.rows ; i++ ) {
+			let sum = 0;
+			for ( let j = 0 ; j < mat.cols ; j++ ) {
+				sum += mat.data[ i ][ j ] * vec.data[ j ];
+			}
+			result.data[ i ] = sum;
+		}
+		return result;
+	}
+}