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I'm currently working with PostgreSQL and CartoDB to display X and Y coordinates converted to a geom. My shp files have been created and are displayed through CartBD.

When I try and run a map view, the points are displayed in relation to each other accurately, they're simply in the wrong position on a global map.

Incorrect SRID

As you can see in the image, the points are there, but they should be within the bounds of Washington DC. The SRID's I have used are 4326, 2248, 2804, and 2893.

Some example points are below:

  • "blocksiteaddress" | "blockxcoord" | "blockycoord"

  • "2516 - 2599 BLOCK OF NAYLOR ROAD SE" | "402548" | "133051"

  • "10 - 199 BLOCK OF DANBURY STREET SW" | "399075" | "128889"
  • "1700 - 1799 BLOCK OF I STREET NW" | "396480" | "137054"

Is there a method for obtaining or deciphering what ESRI/SRID code would best fit my data?

  • Your edit has actually removed some useful information from the question, particularly which SRIDs you've tried. But the most important piece of information missing is what is the source of your xy coordinates? Are they from a consumer GPS? Another data source that had a particular projection? Your basic question seems to be 'how do I identify the CRS of my data', which we have a few different questions on. Even providing example coordinates could help identifying the proper CRS if you don't know the source. – Chris W Nov 10 '15 at 21:30
  • @ChrisW - You're right. I've added the SRID's as well as a few coordinates. The source is data.octo.dc.gov. – user62118 Nov 10 '15 at 22:25
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    2804 works for me. That is, any NAD83 variant of the Maryland state plane zone that uses meters (not US feet) should work within a foot or so. – mkennedy Nov 11 '15 at 0:31
  • @mkennedy - I've tried 2804 and the image above is the result. I converted the coords to a geom before uploading to CartoDB using the link below: twiav-tt.blogspot.com/2012/07/… Is there a reason we're getting a different result? – user62118 Nov 11 '15 at 14:50
  • I'm hitting my knowledge limit! Ah hah, the map is using 2248 (MD state plane in feet), but the coordinates are in meters. Run through the linked tutorial again, but use 2804. Or if you put a call to ST_Transform in the right place (I don't know where), you could convert the coordinates to 2248 or 4326. – mkennedy Nov 11 '15 at 16:58

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