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I have a vector layer (points) that I rasterized based on one attribute of the vector layer. I chose the GRASS GIS 7 command : v.to.rast.attribute. The raster layer appears in the map, but is not very readable.

Here is the original vector layer (points) :

enter image description here

Here is the rasterized result (based on one attribute of the layer) :

enter image description here

I would like to make the points bigger in the raster.

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Raster format is not the best format to display points: you should display your data with points. That being said, you have two solutions :

1) change the rasterization settings by selecting a larger pixel size as an output. With v.to.rast you must first define the resolution of the region ( g.region vector=your_vector res=5000 -p -a), with gdal_rasterize you can use the -tr option). Points will look like squares.

2) create buffers (polygons) aroud your points and convert the buffers to raster. You will have circles, but one point will give you more than one pixel.

In both cases, you will have only one value per pixel, so this might be an issue when your points symbols currently overlap

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    The thing is that the points (villages) contain in their attribute table two columns: elevation and pop density. I want to see in a map these points (villages) according to their elevation and then their pop density. Meaning that a village with high elevation would be in red, village with medium elevation in orange and village with low elevation in white. The same for pop density. Ideally in the end cross those two results to finally target just villages with low land elevation and high pop density. – Janita Jun 14 '16 at 10:05
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    I think that you should ask another question on the best way to symbolize a vector with two fields. Converting to raster will not help. Have a look at this post first gis.stackexchange.com/questions/174405/… – radouxju Jun 14 '16 at 10:11
  • Thanx a lot, I've just used the rule based style for the layer (described in the link) and it looks good. One of the rules is Low elevation & High population density, that shows me the targeted villages. In order to see those villages nicely in a country scale, I'll put the selection in another layer and transform him into a heatmap, thanks to the heatmap plugin. It works pretty good. – Janita Jun 14 '16 at 13:30

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