Xirtam

Installation

npm install xirtam

Usage

Most of the methods in Xirtam returns a new matrix object and allows for methods to be stacked after one another.

var Matrix = require("xirtam");
 
var m1 = new Matrix([[1, 2, 3], [3, 4, 5], [8, 1, 2]]);
var m2 = new Matrix([[23, 52, 1], [45, 6, 5], [3, 1, 7]]);
 
var result = m1
        .add(m2)
        .scalarMultiply(3)
        .multiply(m1);
 
result.prettyPrint();
 

Outputs

654, 804, 1050
474, 438, 642
267, 117, 183

API

Constructor

new Matrix()

Creates a new Matrix instance, accepts a multidimensional array:

var myFirstMatrix = new Matrix([[1,0],[0,1]]);
var mySecondMatrix = new Matrix([[1,2],[3,4]]);

Properties

matrix.rows

The rows property contains the number of rows for the respective matrix instance

var rows = myFirstMatrix.rows;

> console.log(myFirstMatrix.rows);
2

matrix.cols or matrix.columns

The cols property contains the number of columns for the respective matrix instance, columns is an alias for this property.

var cols = myFirstMatrix.cols;
var cols = myFirstMatrix.columns;

> console.log(myFirstMatrix.cols);
2

matrix.data

The data property contains the actual data of the matrix instance, i.e: the double array of the values in the matrix.

var data = myFirstMatrix.data;

> console.log(myFirstMatrix.data);
[[1,0],[0,1]]

Methods

The following methods will return a new matrix object.

matrix1.add(matrix2)

Creates a new matrix by adding each respective term in the matrices. Each of the matrices must be of the same dimensions, i.e: the same number of rows and columns. If these are different an error will be thrown.

var result = myFirstMatrix.add(mySecondMatrix);
result.prettyPrint();

 2, 2
 3, 5

matrix1.subtract(matrix2)

Creates a new matrix by subtracting each respective term in the matrices. Each of the matrices must be of the same dimensions, i.e: the same number of rows and columns. If these are different an error will be thrown.

var result = myFirstMatrix.subtract(mySecondMatrix);
result.prettyPrint();

 0, -2
 -3, -3

matrix1.elementWiseMultiplication(matrix2)

Creates a new matrix by multiplying each respective term in the matrices. Each of the matrices must be of the same dimensions, i.e: the same number of rows and columns. If these are different an error will be thrown.

var result = myFirstMatrix.elementWiseMultiplication(mySecondMatrix);
result.prettyPrint();

 1, 0
 0, 4

matrix1.multiply(matrix2, flip)

Creates a new matrix by doing matrix multiplication between the two given matrices. The dimensions of the given matrices must either be same, or the columns of the first matrix must be equal to the rows of the second matrix. Will return a new matrix with rows equal to the number of rows of the first matrix and the number of columns equal to the number of columns of the second matrix.

var result = myFirstMatrix.elementWiseMultiplication(mySecondMatrix);
result.prettyPrint();

 1, 2
 3, 4

If the the second argument, flip, is set to true then the matrices will be flipped.

var result = myFirstMatrix.elementWiseMultiplication(mySecondMatrix, true);
result.prettyPrint();

 1, 2
 3, 4

matrix1.scalarMultiply(scalar)

Creates a new matrix where each element of the matrix1 is scaled by the given scalar.

var result = myFirstMatrix.scalarMultiply(2);
result.nicePrint();

 2, 0
 2, 2

matrix1.transpose()

Creates a new matrix that is the transpose of matrix1

var result = mySecondMatrix.transpose();
result.nicePrint();

 1, 3
 2, 4

Data manipulation methods

matrix1.each(function(element, row, column))

Will run through each element of matrix1 and call a function on each of the elements, the returned value from this function will replace the element at that row and column position.

var result = myFirstMatrix.each(function(){
    return 2
});
result.nicePrint();

 2, 2
 2, 2

Data getters/setters methods

matrix1.setDataPoint(row, column, data)

Sets the element found at row, column to the given data.

var result = myFirstMatrix.setDataPoint(0, 0, 2);
result.nicePrint();

 2, 0
 0, 1

matrix1.getRow(row)

Returns a row of matrix1.

console.log(myFirstMatrix.getRow(0));

[1, 0]

matrix1.getDataPoint(row, column) or matrix1.get(row, column)

Returns a data element found at row, column in matrix1. get is an alias for getDataPoint.

console.log(myFirstMatrix.get(0, 0));

1

Miscellaneous methods

matrix1.copy() or matrix1.clone()

Returns a copy of the matrix

var result = myFirstMatrix.clone();
result.nicePrint();

 1, 0
 0, 1

matrix1.foreach(function(element))

This method will call the given function with each of the elements in the matrix

var sum = 0;
var result = myFirstMatrix.foreach(function(){
    sum ++;
});
console.log(sum)

4

matrix1.prettyPrint() or matrix1.nicePrint()

This function will print the matrix data out in matrix format

myFirstMatrix.prettyPrint()

 1, 0
 0, 1

matrix1.equals(matrix2)

This method compares matrix1 to a given matrix, matrix2, and returns true if they are equal. Checks the data within the matrices.

var result = myFirstMatrix.equals(mySecondMatrix);
console.log(result)
 
var result = myFirstMatrix.equals(myFirstMatrix);
console.log(result)

false
true