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I am trying to import a GeoTiff (.tif) into GRASS GIS. I then want it to show up in the map display.

This is the data I want to use: http://ghsl.jrc.ec.europa.eu/ghs_pop.php

As far as I can tell, this is raster data. I know the location and the dataset must share the same projection. When I set up the location, I selected "Read projection and datum terms from georeferenced file". GRASS GIS correctly read projection and datum.

Now, I selected the location I just created, and the predefined mapset "PERMANENT". Then I hit "Start GRASS Session".

But now I'm just seeing a purple rectangle. See this screenshot:

enter image description here

I'm not quite sure what's going wrong.

Background: I am to visualize the population growth in south america. Our college course didn't do anything to prepare me for this so I have to ask such basic questions.

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After importing the dataset into GRASS, you will need to complete two more steps. First, you should set the value of 0 to null. This can be done from the command-line as follows:

r.null map=GHS_POP_GPW41975_GLOBE_R2015A_54009_1k_v1_0 setnull=0

When you visualise your dataset, you should see something that broadly resembles the map of the world:

enter image description here

You then need to set the color table using either r.colors or from the menu as follows (right click --> Set Color Table):

r.colors -e map=GHS_POP_GPW41975_GLOBE_R2015A_54009_1k_v1_0@PERMANENT color=viridis

enter image description here

Which will render the map as follows:

enter image description here

Note: you will need to configure your color scheme using a pre-existing colour style or by defining your own rule set. More information regarding r.colors is available here

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