I am new to QGIS and I am trying to import more than 700 xyz (it is the same as ASCII?) files into the map so I can get a digital elevation model and then get the average elevation for some small polygons. I can simply import individual xyz file but importing more at once doesn't work for me?

I would like to make something such as a virtual raster catalog but I get Warning 6: gdalbuildvrt does not support positive NS resolution.

My files look like this: (they have no headers)

383000.0 97000.0 83.30

383005.0 97000.0 82.80

383010.0 97000.0 82.70...

Ivan

I am new to QGIS and I am trying to import more than 700 xyz (it is the same as ASCII?) files into the map so I can get a digital elevation model and then get the average elevation for some small polygons. I can simply import individual xyz file but importing more at once doesn't work for me?

I would like to make something such as a virtual raster catalog but I get:

Warning 6: gdalbuildvrt does not support positive NS resolution.

My files look like this: (they have no headers)

383000.0  97000.0   83.30
383005.0  97000.0   82.80
383010.0  97000.0   82.70...