[Qgis-user] rasterization and raster analysis

[Ramon Andinach]

On 12/04/2011, at 22:11 , Julio Cesar Canales DElgadillo wrote:

> Hello there Qgis people,
> I have a couple of questions about the use of GDAL tools. I tried to rasterize some vector layers using the rasterize tool of GDAL, but it  is not clear for me what means: "output file for rasterized vectors (raster, must exist)", I have no a raster for these areas (and this is the reason I wish to create it), may be I'm not understanding something but I do not what it is, somebody knows about it or knows where to find a tutorial on this function?
> Do you know if there is some way to analize with  Qgis the connectivity between different classes in a raster (categorical raster), something like fragstats does? If yes I will be so grateful for any information about it.
> Best wishes.
> Biól.MCF. Julio César Canales Delgadillo.

I know what it means, but I don't know (yet) an easy way around it (does anyone here have any *easy* suggestions?).

Up to version GDAL library version 1.8, GDAL is not able to make its own rasters. Therefore, GDAL expects a raster of the right size and projection to exist for GDAL write into.
If you're using trunk (1.7) on windows GDAL 1.8 is available and you can ignore this.

-ramon.