cluster on lists of values that start with a certain value

def grouper(iterable):<br /> prev = None<br /> group = []<br /> for item in iterable:<br /> if not prev or item – prev <= 15:<br /> group.append(item)<br /> else:<br /> yield group<br /> group = [item]<br /> prev = item<br /> if group:<br /> yield group</p> <p>numbers = [123, 124, 128, 160, 167, 213, 215, 230, 245, 255, 257, 400, 401, 402, 430]<br /> dict(enumerate(grouper(numbers), 1))