Print dict items in alphabet order

Question

I'm working on my python script to dict the channels items every time when the items is inserted by using this code:

channels = {}
for elem in tv_elem.getchildren():
    if elem.tag == 'channel':
       channels[elem.attrib['id']] = self.load_channel(elem)
       for channel_key in channels:
           channel = channels[channel_key]
           display_name = channel.get_display_name()
           print display_name

Here is what it print out:

20:58:02 T:6548  NOTICE: BBC One UK EN
20:58:02 T:6548  NOTICE: SVT 1 SE SE
20:58:02 T:6548  NOTICE: National Geographic Channel UK EN
20:58:02 T:6548  NOTICE: NRK1 NO NO
20:58:02 T:6548  NOTICE: Discovery Channel UK EN
20:58:02 T:6548  NOTICE: ARD DE DE
20:58:02 T:6548  NOTICE: DR1 DK DK

Here is the XML file:

<?xml version="1.0" encoding="UTF-8" ?>
<tv generator-info-name="www.timefor.tv/xmltv">
        <channel id="www.timefor.tv/tv/162">
            <display-name lang="de">ARD DE DE</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/1">
            <display-name lang="dk">DR1 DK DK</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/130">
            <display-name lang="no">NRK1 NO NO</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/135">
            <display-name lang="se">SVT 1 SE SE</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/10769">
            <display-name lang="en">BBC One UK EN</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/10214">
            <display-name lang="en">National Geographic Channel UK EN</display-name>
        </channel>
        <channel id="www.timefor.tv/tv/10847">
            <display-name lang="en">Discovery Channel UK EN</display-name>
        </channel></tv>

I want to print them in the same alphabet order as the XML file, what I have print it is not in the same order as the XML file. Do you know how I can print the items in the same alphabet order as the XML file using my code?

A `dict` is essentially unordered. Try using an [OrderedDict](http://docs.python.org/2/library/collections.html#collections.OrderedDict) — Tejas Pendse, Mar 10 '14 at 16:27
It doesn't seem that the xml file is sorted alphabetically (either by `tv/xxxxx` or `display-name`. Is this intended? — wflynny, Mar 10 '14 at 16:27
@mogambo thank you for your advice. Could you please post the source of the OrderedDict with my code that I should use? — , Mar 10 '14 at 16:30
Do you want the same ordering as the XML, or do you want to sort the channels by display name? — Steinar Lima, Mar 10 '14 at 16:30
And should `for channel in channels` be inside the other `for` loop? It doesn't make any sense. — Steinar Lima, Mar 10 '14 at 16:31
You could just use a list if order rather than lookup is important — EdChum, Mar 10 '14 at 16:32
@SteinarLima yes I'd want the same ordering as the XML, but if that is not possible then listing the channels in OrderedDict would be great. — , Mar 10 '14 at 16:33

Tejas Pendse · Accepted Answer · 2014-03-10T16:52:56.470

3

Based on what you've explained:

#Additional import
from collections import OrderedDict
channels = OrderedDict()
for elem in tv_elem.getchildren():
    if elem.tag == 'channel':
       channels[elem.attrib['id']] = self.load_channel(elem)
       for channel_value in channels.items():
           print channel_value.get_display_name()

NOTE: This will give you the same order as you read them from the XML, not alphabetical

EDIT : Since you're using Python 2.6, a small workaround:

channels = []
for elem in tv_elem.getchildren():
    if elem.tag == 'channel':
       channels.append( (elem.attrib['id'], self.load_channel(elem)) )
       for channel_value in channels:
           print channel_value[1].get_display_name()

edited Mar 10 '14 at 16:52

answered Mar 10 '14 at 16:36

Tejas Pendse

551
6
19

Thanks for this, but I have got a problem. I have got an error `from collections import OrderedDict ImportError: cannot import name OrderedDict.` I don't know why I have got an error? I'm using python 2.6 version for xbmc. – Mar 10 '14 at 16:47
Unfortunately, `OrderedDict` was introduced in Python 2.7. I guess you'll have to use nested lists. – Tejas Pendse Mar 10 '14 at 16:50
1

OrderedDict was added to the `collections` module in Python 2.7. http://docs.python.org/2/library/collections.html#collections.OrderedDict Use this recipe if you're using Python 2.6: http://code.activestate.com/recipes/576693/ – IceArdor Mar 10 '14 at 16:50
@IceArdor Thank you very much for your help. It have helping me to solve the problem. I have got the list of items that are in perfect alphabet order as the XML file. – Mar 10 '14 at 17:33

score 1 · Answer 2 · answered Mar 10 '14 at 16:42

1

Update: mogambo got in first while I was typing :)

Replace first line with

from collections import OrderedDict
channels = OrderedDict()

I would only add: you might just as well append your channel objects to a list, if you never need to retrieve them individually by id and only want to iterate over them in the same order as they appeared in the XML.

answered Mar 10 '14 at 16:42

scav

1,095
1
9
17

scav is correct in stating that if you don't need constant-time lookup to an individual item in your dictionary then you might as well use a list, which is more memory efficient. – IceArdor Mar 10 '14 at 17:53

Print dict items in alphabet order

2 Answers2