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I have a CSV file with X/Y coordinates that I would like to reproject to have long/lat coordinates. Unfortunatelly, reprojecting or setting CRS does not work.

I have a layer of polygons which is correctly projected (EPSG: 4326), showing coordinates in degrees:

enter image description here

I have another layer of points, which appears in the correct CRS (EPSG: 4326), but the coordinates appear in X/Y.

This points should appear on top of the previous polygon layer:

enter image description here

I have tried to:

  • Change the CRS on the layer properties
  • Set the CRS of the layer
  • Toolbox -> Define layer projection
  • Toolbox -> Reproject layer

I have tried with the on memory layer, saving it as CSV, saving it as SHP and reimporting...

What am I missing?

QGIS version 3.8.0-Zanzibar

enter image description here

  • I assume when importing the CSV you chose the correct Geometry CRS? – AWGIS Jul 29 at 10:21
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The CRS and coordinates you have ringed in red in the images are not the CRS and coordinates of the layer itselft but of the data frame (ie the project's over-arching coordinate system).

Changing the CRS of the layer's properties will not reproject the data (a common misconception). It only changes how the existing coordinates are interprested and presented. You need to save a new version and select a new CRS at that point. Likewise, defining the projection from the toolbox will do a similar thing. It just tells QGIS what the CRS is without changing any actual coordinates (no reprojection).

When you reimport the new data layer it will display in the project's CRS unless you change that (you can right-click the layer and go Set CRS->Project CRS from layer. Otherwise, if you leave the proect CRS as 4326, then the coordinates at the bottom of the map pane will always appear in decimal degrees.

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With help from the answer of @MappaGnosis, the polygon layer was projected on "EPSG:2056 - CH1903+ / LV95". I managed to make it work by projecting the point layer to "EPSG:2056 - CH1903+ / LV95".

  • Import CSV file
  • Chant CRS to "EPSG:2056 - CH1903+ / LV95" The points appear ok on top of the polygons
  • Reproject layer
  • Add geometry attributes
  • Export to CSV
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When you import you point layer, make sure you import it in the right CRS (your source CRS is obviously not 4326, maybe WGS84?). After your import, export it again. Now is the time to change the CRS - in the export menu chose in the drop down menu EPSG 4326 and voila, your point layer should now be in the desired CRS.

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