isApproximatelyEqualTo(other, epsilon) {
        return other instanceof Matrix &&
            this._width === other._width &&
            this._height === other._height &&
            Math.sqrt(this.minus(other).norm2()) <= epsilon;
    }
Determines if the receiving matrix is approximately equal to the given matrix.
@param {!Matrix|*} other
@param {!number} epsilon Maximum distance between the two matrices.
@returns {!boolean}