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How to include Paris 20 administrative district data?  XML
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Anjyu



Joined: 21/08/2007 08:12:52
Messages: 4
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Paris holds 20 administrative district within her.
However, when I download data from geonames, it does not include this district info. I am wondering if there anyway I can include this administrative district data (can be number like 6e or name like Montmartre).

Does anyone has an idea?

Thanks.
samokk



Joined: 13/10/2006 21:56:39
Messages: 82
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Hi,

District data is sometimes present in geonames as "PPLX" features, which means Section of Populated Place. (See : http://www.geonames.org/export/codes.html ).
You can find some of these PPLX here
:
http://www.geonames.org/advanced-search.html?q=paris&country=FR&featureClass=P&continentCode=

The problem I see with the way this data is structured is that the PPLX are not strongly linked with their respective PPL*. So, you basically have to pre-process the data to get the relationships, and the methodology for doing this is not really clear... I think marc said once in the forums that he was basically doing GIS queries around (e.g. 10km) the PPLX, sort the PPL's by population, and link the PPLX to the most populated PPL.

This should work in most cases, since there are rarely 2 cities that both have PPLx and are distant by less than 10/20 km...

Cheers,
Sami
marc



Joined: 08/12/2005 07:39:47
Messages: 3993
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A file with ppl to pplx relation is available here :
http://download.geonames.org/ppl_pplx.csv.gz

As Sami said it has been automatically generated searching for the closest PPL for every PPLX. For Paris is returns 38 PPLX instead of the 20 expected PPLX (arrondissement)

Cheers

Marc

[WWW]
Anjyu



Joined: 21/08/2007 08:12:52
Messages: 4
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Thanks guys.
I will try that.
Anjyu



Joined: 21/08/2007 08:12:52
Messages: 4
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I checked Paris data with PPL* feature code.
Here, Paris data means, admin1_code ='A8' and admin2_code = '75' and country_code='FR'.
Those PPL* data is not much. (below is data count)
PPL 7
PPLC 1
PPLX 27

PPLC data was the data of "Paris", which is bigger idea than PPLX.
PPL data was the data of "commune", which is outside of 20 municipal arrondissements of Paris.

Thus, instead of using PPL-PPLX relation data, I simply used PPLX data ( excluding non municipal arrondissements data) to find nearest municipal arrondissements.
It seems it's working OK so far.

Hope this will help others somehow...

Thanks.
david masclet



Joined: 26/11/2007 11:49:58
Messages: 67
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hi

i can not access the http://download.geonames.org/ppl_pplx.csv.gz file.

it will be great to have it

thanks

David
[WWW]
samokk



Joined: 13/10/2006 21:56:39
Messages: 82
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Hi David,

the file that marc posted was a temporary dump. It does not really make sense to import this file as it may already be out of date.

The best strategy is probably to use the same algorithm as marc to attach the PPLX to their respective PPL :

-> For each PPLX being imported, search for the most populated city (PPL, PPLC, ...) within 10 km. Attach the PPL to this city
marc



Joined: 08/12/2005 07:39:47
Messages: 3993
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I have regenerated the file with the newest data. It is available again with the link : http://download.geonames.org/ppl_pplx.csv.gz

Marc

[WWW]
 
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