function realmax( dtype ) {
	switch ( dtype ) {
	case 'float64':
		return FLOAT64;
	case 'float32':
		return FLOAT32;
	case 'float16':
		return FLOAT16;
	default:
		throw new TypeError( format( 'invalid argument. Must provide a recognized type. Value: `%s`.', dtype ) );
	}
}
Returns the maximum finite value capable of being represented by a numeric real type.

@param {string} dtype - numeric type
@throws {TypeError} must provide a recognized numeric type
@returns {number} maximum finite value

@example
var m = realmax( 'float64' );
// returns 1.7976931348623157e+308

@example
var m = realmax( 'float16' );
// returns 65504.0

@example
var m = realmax( 'float32' );
// returns 3.4028234663852886e+38