Slow comparison between two lists

[Bruno Desthuilliers]

Jani Tiainen a écrit :
> I have rather simple 'Address' object that contains streetname,
> number, my own status and x,y coordinates for it. I have two lists
> both containing approximately 30000 addresses.
> 
> I've defined __eq__ method in my class like this:
> 
>     def __eq__(self, other):
>         return self.xcoord == other.xcoord and \
>             self.ycoord == other.ycoord and \
>             self.streetname == other.streetname and \
>             self.streetno == other.streetno
> 
> But it turns out to be very, very slow.
> 
> Then I setup two lists:
> 
> list_external = getexternal()
> list_internal = getinternal()
> 
> Now I need get all all addresses from 'list_external' that are not in
> 'list_internal', and mark them as "new".
> 
> I did it like this:
> 
> for addr in list_external:
>     if addr not in list_internal:
>         addr.status = 1 # New address
> 
> But in my case running that loop takes about 10 minutes. What I am
> doing wrong?

mmm... not using sets ?