I am running a script that is producing a very large number of layers. As it takes a while, I wanted to find out how many layers were already created using the command line. Trivial thing perhaps, but I wasn’t really sure how to do it. After a bit of search, one way I found uses the versatile awk command line tool. Continue reading
Did you ever add a legend to your categorical raster map in GRASS GIS that displayed many more categories than your map actually has? It can happen if that map was ‘cut out’ from a larger region using r.mapcalc. For example, if I have a vegetation map of eastern Africa, and I need one for Rwanda only. I would do something like: Continue reading
GRASS GIS 7.0.1 RC1 is the upcoming stability release and provides a series of stability fixes, manual improvements and a few language translations. This first release candidate GRASS GIS 7.0.1RC1 provides 168 fixes and improvements with respect to GRASS GIS 7.0.0. See here the announcement and further information.
If you want to help testing or just want to make sure to have all the latest improvements and fixes, go to the announcement page where you’ll find the download links for your system.
In a recent post Anita Graser (aka underdark) showed how to create illuminated or Tanaka contours in QGIS using various functions available in the toolbox and some custom functions.
Here I want to explore a slightly different way to achieve the same, using GRASS GIS to compute the azimuth, brightness and line width. I’ll use the command line, but you can do the same using the menu in GRASS, or the corresponding GRASS functions in the QGIS processing toolbox.
Just a thumbs-up for the developers of GRASS GIS, who evidently do not rest on their laurels since their release of GRASS GIS 7.0. Below one of those more visible new features in the GRASS GIS development version which make live just that much easier.
The data set
The Global Land Cover Facility offers, amongst many other data sets, the MODIS Vegetation Continuous Fields data set for download. These are layers that contain proportional estimates for vegetative cover types (woody vegetation, herbaceous vegetation, and bare ground). As such they are very suitable depict areas of heterogeneous land cover.
Their MODIS products differ from DAAC editions by coming in GeoTIFF format, geographic coordinates, WGS84 datum, and a tiling system designed to fit well with Landsat imagery. Currently the collection 5 is available, which contains proportional estimates for woody cover vegetation for the years 2000 to 2010. It can be downloaded as tiles (195 in total) via a ftp server.
Below I’ll provide an example Continue reading