On Fri, Jun 24, 2011 at 8:01 AM, kaustubh joshi <kandrjo...@gmail.com> wrote: > Hey all, > I am new here and new to python too. In general new to programming . > I was working on aproblem. > and need some help. > I have a list of numbers say [2,3,5,6,10,15] > which all divide number 30. > Now i have to reduce this list to the numbers which are prime in number. > i.e. > [2,3,5] > can somebody suggest?
Well, you can use a built-in function called "filter" to create a list containing only values that meet a certain need, for example, this will filter out everything that is even and put it into a new list - >>> numbers = [1,2,3,4] >>> def is_even(n): return n%2==0 # returns true if even, false if not. >>> filter(is_even,numbers) [2, 4] All you need to do is to create or adapt an algorithm that tests whether a number is prime or not, and use that along with filter on your list of numbers. Several examples exist, it's quite a popular question. HTH. Noah. -- http://mail.python.org/mailman/listinfo/python-list