[Qgis-user] zonal statistics with multiple bands raster

[Xavier Vollenweider]

Dear all,

Some progresses, the following little code does what I need for the first band (i.e. day) I think:

import qgis.analysis
vectorlayer=qgis.utils.iface.mapCanvas().layer(0)
rasterfile = qgis.utils.iface.mapCanvas().layer(1).source()
zonalstats = qgis.analysis.QgsZonalStatistics(vectorlayer,rasterfile,str(1))
zonalstats.calculateStatistics(None)

I would like know to loop over the 11117 days with something like:
Day=range(1,11117,1)
for i in Day:

My question is hence: how do I access the other bands?
This doesn't work for instance: rasterfile = qgis.utils.iface.mapCanvas().layer(data at 1).source()

All the best,

Xav


From: qgis-user-bounces at lists.osgeo.org [mailto:qgis-user-bounces at lists.osgeo.org] On Behalf Of Xavier Vollenweider
Sent: vendredi 9 août 2013 14:18
To: qgis-user at lists.osgeo.org
Subject: [Qgis-user] zonal statistics with multiple bands raster

Dear all,

I would like to compute zonal statistics from a raster file with multiple bands (11'117 actually). The raster file (.cdf) contains daily rainfall for Kenya from 1983 to present. I need to get the average rainfall for each county.

I know how to do it manually for each band, but doing it on the  11'117 bands is clearly not option...

Could you provide me with a way to automatize it via the python console?

Ideally, I would like the end result should be a shape file with the 11'117 attributes that I will eventually save as a .csv. The goal is to build a panel dataset that I will use in R or Stata.

All the best,

Xav
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