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saxrub



Joined: 12/05/2019 09:35:56
Messages: 3
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Hello

I'm working on a project for a census of the biodiversity of the small islands of the Mediterranean.

I must add the administrative repositories (regions, departments, communes ...) in the French reference system which has been operational for several years.

I work on two axes:

1 - extract the administrative references of the 'free gazetteer data' data from the Mediterranean countries.
2 - use reverse georeferencing with extendedFindNearbyJSON to retrieve the administrative hierarchy of the point.

It was during my research that I found errors or inconsistencies for Tunisia (I also worked on Spain).

1 - TN.txt file: value of the "Admin1 code".
If the indicated values ​​are consistent in the TN.txt file, and more generally in geonames, these do not correspond to the official values ​​of Tunisia http://www.ins.nat.tn/sites/default/files/publication /pdf/codegeo_2013.pdf.
For example, the Protectora of Sfax is noted 32 in the file TN.txt whereas the good nomenclature is 34, that of Bizerte is noted 18 whereas the good code is 17. It is as if Paris 75 was noted 13 (Bouches -du-Rhône)!
2 - extendedFindNearbyJSON: To understand the returned data, I took random coordinates located on an island off Sfax.
Here is the URL used: http://api.geonames.org/extendedFindNearbyJSON?lat=35.79811&lng=11.03576&username=saxrub
In the returned data, we see that the place is named "Sidi el Rhedamsi" (last node of the JSON type PPL) with geonameID 2466533. First surprise, this node is directly linked to a geoname 2473495 (Monastir Governorate) having a fcode ADM1 (unlike continental coordinates or ADM2 is always returned).
Unless this link is the reality linked to the history of Tunisia, note that Monastir is 120km and Sfax 20km!
Not being a specialist in Tunisia, I can not know what he is going back to. Could you join a Tunisian specialist?
3 - For each country, a hierarchie.txt file is provided. However, it turns out that the geonameID 2466533 mentioned in point 2 is not present in the hierarchie.txt file.
Here are my questions and comments, I hope I have been clear in my explanations!

Looking forward to your answer.

cordially

Pascal
marc



Joined: 08/12/2005 07:39:47
Messages: 4154
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- The admin1 code normally is the international fips code. For lower levels the national codes are used.

- your lat/lng are near Monastir. The responses look correct. The closest ppl does not have an adm2 code because we don't know to which adm2 it belongs. If you know, please feel free to update.

- the hierarchy file is for additional relations outside of the admin hierarchy. The admin hierarchy is encoded in the adm codes.

Marc

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