It seems that SAGA GIS stores angles (slope, aspect) in internally
radian, but it shows them in degrees when displaying them in the GUI of
SAGA GIS. I noticed that once in the context of slope angles and was
pretty puzzled... just do *180/pi to convert radian into degree.
A.
gianni lavaredo wrote:
Dear Professor,
Thanks for your competence and your work in RSAGA and Rypgeo. This packages
are very useful and interesting.
I am testing different geoprocessing code in RSAGA, SAGA, Phyton and Rypgeo
to see the results, but I noticed a singular situation. I am using this code
to create SLOPE and ASPECT with DEM in RSAGA and see the difference in
ARCGIS geoprocessing
rsaga.slope("DEM","SLOPErad")
# convert to slope in percent:
rsaga.grid.calculus("SLOPErad","SLOPE", formula="100*tan(a)")
rsaga.sgrd.to.esri("SLOPE", prec = 4)
rsaga.aspect("DEM","ASPECT")
rsaga.sgrd.to.esri("ASPECT", prec= 4)
but there are some difference when I convert the ASPECT.sgrd in ASCII file.
ex
ASPECT.sgrd: min value= 0.020869 max value = 360.00001
(the same Value range I have in SAGA GIS or in ARCGIS)
ASPECT.asc: min value= 0.0004 max value= 6.2832
Thanks Again
Gianni
--
Alexander Brenning
brenn...@uwaterloo.ca - T +1-519-888-4567 ext 35783
Department of Geography and Environmental Management
University of Waterloo
200 University Ave. W - Waterloo, ON - Canada N2L 3G1
http://www.fes.uwaterloo.ca/geography/faculty/brenning/
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