Ju Hui wrote: > I want to remove about 50000 elements from a list,which has 100000 > elements. > sample code like below: > >>>> a=range(10) >>>> b=range(4) >>>> for x in b: > ... a.remove(x) > ... >>>> a > [4, 5, 6, 7, 8, 9] > > when a and b is small size, it will finished quickly, but when a and b > have many elements. > such as: >>>> a=range(100000) >>>> b=range(50000) >>>> for x in b: > ... a.remove(x) > ... > it will very slowly. Shall I change to another data structure and choos > a better arithmetic?
How about a listcomprehension? new_list = [e for e in old_list if predicate(e)] # Possibly you need this, too: old_list[:] = new_list Diez -- http://mail.python.org/mailman/listinfo/python-list
