Fredrik Lundh wrote: > Neil Cerutti wrote: > > >> bisect... > > > > That doesn't tell me if an item doesn't exist in the sequence > > though, does it? Maybe I'm being dense. > > I guess you could use something like > > import bisect > > def check(list, item): > try: > return list[bisect.bisect_left(list, item)] == item > except IndexError: > return False > > but unless your lists are really large, or your objects are expensive to > compare, you could probably just use "in" instead. > > > My guess nobody keeps their sequences sorted in Python. > > well, people tend to use dictionaries when they need to look things up > quickly...
... like those paper dictionaries with the words in alphabetical order :-) A common use case for looking things up in a sorted list is an in-memory table of dates and rates (interest rates, insurance premium rates, fee rates). In a big batch job, this sure beats doing "select rate from table where ? between low_date and high_date" each time you need a rate. Cheers, John -- http://mail.python.org/mailman/listinfo/python-list
