constructor( n11, n12, n13, n21, n22, n23, n31, n32, n33 ) {

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		Matrix3.prototype.isMatrix3 = true;

		/**
		 * A column-major list of matrix values.
		 *
		 * @type {Array<number>}
		 */
		this.elements = [

			1, 0, 0,
			0, 1, 0,
			0, 0, 1

		];

		if ( n11 !== undefined ) {

			this.set( n11, n12, n13, n21, n22, n23, n31, n32, n33 );

		}

	}
Constructs a new 3x3 matrix. The arguments are supposed to be
in row-major order. If no arguments are provided, the constructor
initializes the matrix as an identity matrix.

@param {number} [n11] - 1-1 matrix element.
@param {number} [n12] - 1-2 matrix element.
@param {number} [n13] - 1-3 matrix element.
@param {number} [n21] - 2-1 matrix element.
@param {number} [n22] - 2-2 matrix element.
@param {number} [n23] - 2-3 matrix element.
@param {number} [n31] - 3-1 matrix element.
@param {number} [n32] - 3-2 matrix element.
@param {number} [n33] - 3-3 matrix element.