function nextDataType( dtype ) {
	if ( arguments.length === 0 ) {
		return generateTable();
	}
	dtype = resolveStr( dtype );
	if ( hasOwnProp( NEXT_DTYPES, dtype ) ) {
		return NEXT_DTYPES[ dtype ];
	}
	return null;
}
Returns the next larger ndarray data type of the same kind.

@param {*} [dtype] - ndarray data type value
@returns {(Object|string|integer|null)} next larger data type(s) or null

@example
var dt = nextDataType( 'float32' );
// returns 'float64'