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When I try to transform geometries from SRID 2321 to 4326, the transformed coordinates are swapping. Why is this happening?

Below are the details

Source

SRID - EPSG:2321

Source Data Projection Definition:

  • WGS84 Bounds: 31.5000, 35.9000, 34.5000, 42.1000
  • Projected Bounds:364573.0642, 3975550.1410, 635426.9358, 4663916.1654
  • Area: Turkey - 31.5°E to 34.5°E

below are the sample points :

  • 470343.6,4402310.3
  • 470105.0,4402410.8
  • 470236.5,4402700.1

Destination

SRID - EPSG:4326

Below are the sample points after conversion:

  • 32.6539666652,39.753664831
  • 32.6511781435,39.7545616174
  • 32.6526994043,39.7571716999

When I try to project these point on a Google map they are referencing to Iraq when they should refer to Turkey.

But when I tried with reversing the coordinates of the above points then they are referencing to correct locations on Google maps

Why is this happening? Do I miss anything?

EDIT:

Software used for conversion : Spatialite v 4.1.1 and this conversion is confirmed using this link.

Actually my source data is from ESRI personal geodatabase .mdb file. I used QGIS to import them into Spatialite and when I try to project them on google/Apple maps all data is referencing to a different location.

PolyGeo
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venkat530
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  • What do you mean the coordinates are swapping? 32.6539666652,39.753664831 is actually 32.6539666652E,39.753664831N, which does fall in Turkey. I think you might be running into a confusion similar to this: http://gis.stackexchange.com/a/54066/442 – Devdatta Tengshe Feb 07 '14 at 03:08

1 Answers1

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When talking about geographic locations, we usually say and use Lat-long. This has been codified in the ISO 6709 standard.

When dealing with Cartesian coordinate geometry, we generally use X-Y. Many GIS systems, work with a Geographic Location as a special case of a 2 D coordinate point, where the X represents the longitude and Y represents the Latitude. This order of coordinates, is exactly opposite that of the regular Lat-long notion.

SO when Spatialite gives 32.6539666652,39.753664831, it is actually 32.6539666652E,39.753664831N since the first coordinate is X (i.e longitude) & second one is Y (i.e. Latitude).

If you put just 32.6539666652,39.753664831 in Google Maps, it assumes that you are giving coordinates in Lat-Long, and not in XY. It parses the coordinates as: 32.6539666652N ,39.753664831E. That's why it shows you the point in Iraq

So I'll say that this isn't a bug, just a matter of confusing and contradictory standards.

For similar Issues, go through these two Q&A:

Devdatta Tengshe
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