Float32Array concatenation uses buffers

Float32Array.concat.js

Float32Array.prototype.concat = function() {
	var bytesPerIndex = 4,
		buffers = Array.prototype.slice.call(arguments);
	
	// add self
	buffers.unshift(this);

	buffers = buffers.map(function (item) {
		if (item instanceof Float32Array) {
			return item.buffer;
		} else if (item instanceof ArrayBuffer) {
			if (item.byteLength / bytesPerIndex % 1 !== 0) {
				throw new Error('One of the ArrayBuffers is not from a Float32Array');	
			}
			return item;
		} else {
			throw new Error('You can only concat Float32Array, or ArrayBuffers');
		}
	});

	var concatenatedByteLength = buffers
		.map(function (a) {return a.byteLength;})
		.reduce(function (a,b) {return a + b;}, 0);

	var concatenatedArray = new Float32Array(concatenatedByteLength / bytesPerIndex);

	var offset = 0;
	buffers.forEach(function (buffer, index) {
		concatenatedArray.set(new Float32Array(buffer), offset);
		offset += buffer.byteLength / bytesPerIndex;
	});

	return concatenatedArray;
};

var array1 = new Float32Array(10000000),
    array2 = new Float32Array(10000000);

var array3 = array1.concat(array2);