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I have a list of 73 GPS points that represent animal observations. Each point also lists the bearing (angle in degrees) and distance from the observer to the animal. Instead of displaying each point at the recorded GPS location, I would like to display the location of the animal (the location of the GPS point, offset by the distance and bearing recorded with the point). Does anyone know how to move points in this way?

Other solutions on Stack Exchange suggest using a VB script, which I am not familiar with. But I would be happy to try with a breakdown of the steps.

I am using QGIS 2.18.7.

closed as unclear what you're asking by mgri, whyzar, Midavalo Jul 6 '17 at 17:50

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    What other solutions are you referring to? Please edit your question to include links to other solutions you have tried or are having trouble with. – Midavalo Jul 6 '17 at 17:50
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This can be done in a spreadsheet. First your coordinates should be in a projected coordinate system if they are not already so the X and Y units will be in meters.

Then the formula for the new X and Y would be:

NEW_X = OLD_X + (SIN(RADIANS(BEARING)) * DISTANCE)

NEW_Y = OLD_Y + (COS(RADIANS(BEARING)) * DISTANCE)

  • This was the most useful solution which gave me what I wanted. Note a useful solution for converting coordinates in bulk is at hamstermap.com – Nebulloyd Jul 6 '17 at 20:17
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A 'script free' way to do this would be to do the following:

  1. use the field calculator to populate 2 columns, 1 to hold the x coord and the other to hold the y.
  2. export the the attribute table to a csv and open it in excel
  3. create 2 new columns to contain the transformed x and y coords
  4. use trigonometry to calculate the new x and y coord based on distance and bearing
  5. replace the old x and y with the new x and y
  6. load the csv back into QGIS

This solution assumes that your map and distance units are the same.

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