Abandoned <[EMAIL PROTECTED]> wrote: > Hi.. > I have a list as a=[1, 2, 3 .... ] (4 million elements) > and > b=",".join(a) > than > TypeError: sequence item 0: expected string, int found > I want to change list to a=['1','2','3'] but i don't want to use FOR > because my list very very big. > I'm sorry my bad english. > King regards
Try b=','.join(map(str, a)) -- it WILL take up some memory (temporarily) to build the huge resulting string, but there's no real way to avoid that. It does run a bit faster than a genexp with for...: brain:~ alex$ python -mtimeit -s'a=range(4000*1000)' 'b=",".join(map(str,a))' 10 loops, best of 3: 3.37 sec per loop brain:~ alex$ python -mtimeit -s'a=range(4000*1000)' 'b=",".join(str(x) for x i n a)' 10 loops, best of 3: 4.36 sec per loop Alex -- http://mail.python.org/mailman/listinfo/python-list
