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I'm trying to map data for a county in Texas. The data were provided to me in a shapefile, and I've been working with it in QGIS 2.14. My problem is this: The coordinates in the shapefile I was given are wrong. The latitudes should all be in the 31-degrees range, but instead they're around 21 degrees N, which - when exported into Google Earth - puts the county squarely in Mexico.

Is there a way in QGIS that I can simply add ten degrees to all the inaccurate latitude coordinates? Everything else about the shapefile seems correct - it's just the degrees latitude are ten degrees lower than they should be.

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    This may not be the most elegant solution, but you can export the file to excel. Then add 10 degrees to your coordinates. Then geocode the points from your new X,Y – ed.hank Apr 27 '16 at 21:18
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    I would install and try the Affine transformation plugin. – user30184 Apr 27 '16 at 21:23
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    Welcome to GISse! A few things. You received the file as a shapefile from someone else and were using it in QGIS. Did it work fine in QGIS, and by this, I mean, did it overlay with other data properly? Where did the data come from? What projection is it in? When you exported from QGIS, were you actually doing a coordinate transform to Lat/Lon as part of the kml export? Have you spoken to the people who provided you the source data? These are a few things to try, as well as additional information to provide in your question. – Get Spatial Apr 27 '16 at 21:37
  • What might have happened is that it was in a Texas state plane zone, but someone unprojected to lat-lon but using the wrong zone. Except that should have offset the data east-west too. What county? – mkennedy Apr 27 '16 at 22:19
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    Can you add the content of the .prj file, and the extent given by Rightclick on the layer, Properties, Metadata, Properties field? – AndreJ Apr 28 '16 at 5:28
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First install QGIS plugin "Affine Transformation" from Plugins > Manage and Install Plugins..

Then start editing and navigate to vector > Geoprocessing Tools > Affine Transformation. Add your latitude value in 'y+' as encircled in the screen shot.

enter image description here

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    While the answer is technically correct, it misses some information concerning proper assessment of the source of the error. This may result in data that appears to be correct but in fact is wrong. Before resorting to this approach please take the comments on the question into consideration. – Matthias Kuhn Apr 28 '16 at 10:17

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