On Wed, Sep 7, 2011 at 2:57 PM, lina <lina.lastn...@gmail.com> wrote: > On Wed, Sep 7, 2011 at 2:25 PM, Hugo Arts <hugo.yo...@gmail.com> wrote: >> forgot to forward this to list, sorry. >> >> >> ---------- Forwarded message ---------- >> From: Hugo Arts <hugo.yo...@gmail.com> >> Date: Wed, Sep 7, 2011 at 8:24 AM >> Subject: Re: [Tutor] how to sort the file out >> To: lina <lina.lastn...@gmail.com> >> >> >> On Wed, Sep 7, 2011 at 8:16 AM, lina <lina.lastn...@gmail.com> wrote: >>> On Wed, Sep 7, 2011 at 1:28 PM, Hugo Arts <hugo.yo...@gmail.com> wrote: >>>> I was assuming that the numbers were field 1, and the letter/number >>>> combinations were field 2. If I understand him correctly, he wants the >>> >>> Yes. >>> >>>> lines in file 2 to be arranged such that the order of field two is the >>>> same as it is in file 1. In that case, you can do it with one sexy >>>> sort() call (and a little preprocessing to load the files), but I >>>> don't want to get all into explain and then realize he wants something >>>> totally different. >>> You understand right. >>> >> >> Well, it is fairly simple. You grab field2 from file1, and put all the >> items into a list (should be easy right? open(), readlines(), split(), >> grab second item). Then, you grab file2 as a list of tuples (same >> procedure as the first file, but you just put the results of split() >> right into the list. Then you sort with a key like so: >> >> list2.sort(key=lambda x: list1.index(x[1])) >> >> You see? For each item in the second list, we grab field 2, and look >> up what index it has in list1. Then we use that index as the sort key. >> That way they'll be sorted like file1 is. > > not easy to me. > > Sign ... I may do it by hand, cut and pasta following the orders.
After overcoming the nearly-give-up frustration, I finally see the deadly-beautiful results. It's so BEAUTIFUL. amazing ... >> >> After that it's just a matter of writing back to the file, easy peasy. >> >> HTH, >> Hugo >> _______________________________________________ >> Tutor maillist - Tutor@python.org >> To unsubscribe or change subscription options: >> http://mail.python.org/mailman/listinfo/tutor >> > > > > -- > Best Regards, > > lina > -- Best Regards, lina _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
