I have some GPS data for Iran. their stable framework is Arabia. for comparison them with other GPS data, I need to change their framework into Eurasia instead of Arabi. Is there any suggestion for this conversion except calling the authors?
I think what you want to is possible with GPS Plugin in QGIS 3.16. It is not straight forward, but by importing the data and defining coordinate frames for two different data sets it should be able to transform them into a single frame.
I believe what you're asking is how to perform a datum transformation. The GPS module in QGIS can help, but as noted, isn't straightforward all the time. There are external packages you can access. Can you identify the datum the points were collected using?
Gerry Creager and Deneth Karunarathne
thanks for your responding.
unfortunaetly, datum is not mentioned.
But its data is in agreement with another paper that brings its data respect to both Arabi and Eurasia. Is QGIS able to find the Datum through them?
Finding the datum is a more involved process than transforming data into a different datum. At issue is how the data are collected and how the GPS system works. If you consider that you are starting with a coordinate system that is earth-centered and earth-fixed (ECEF)with without reference to a surface, in other words, one that is solely based on the orbital mechanics of the satellites, this starts to make a bit of sense. These "ECEF" data are transformed using a reference datum, which in turn has a reference ellipsoid (describing the shape of the Earth for the purposes of measurement) to provide points in the described space, that usually correspond to "points on the ground". If you know the working datum and reference ellipsoid, you can recreate the ECEF parameters and transform the data to another reference system, but without the starting point it is nearly impossible.
gerry