arcgis-10.1arcgis-desktoprasterspatial-analystzonal statistics
I have a raster file on precipitation and I want to create zonal statistics as a table using a shapefile with boundaries of countries across the world. However it appears that I need to take into account that in different latitudes the corresponding area is different and thus I need to weight my statistic (mean etc.) for area.
Any suggestions on how I can do that?
You need to use the %Name% inline variable for your output table names
For some reason your code is not producing a QgsZonalStatistics object. Print 'zoneStats' to corroborate this. It should be observed some similar to:
<qgis._analysis.QgsZonalStatistics object at 0x9fc316ec>
I tried out the next code:
from qgis.analysis import QgsZonalStatistics
mapcanvas = iface.mapCanvas()
layers = mapcanvas.layers()
provider = layers[1].dataProvider()
path = provider.dataSourceUri()
zoneStat = QgsZonalStatistics(layers[0], path,"", 1, QgsZonalStatistics.Mean)
print zoneStat
zoneStat.calculateStatistics(None)
for this situation:
and, after running the script, it was added only the mean value; as it can be observed at the next image:
It works perfectly for me.
Best Answer
If you are open for other GIS tools then have a look at SAGA-GIS:
http://sourceforge.net/projects/saga-gis/
There is a module called "Grid Statistics for Polygons" which does exactly what you are looking for.