[Qgis-user] ordinary kriging parameters

[Kirk Schmidt]

Hi Maria:

Just from the cuff, the units are pixels or meters.  Try reprojecting 
your source data to a projected coordinate system (UTM, for example) and 
try kriging again.  Set the raster resolution to a course value that 
makes sense for your data to run a test raster and then run at the final 
resolution you require if you are concerned with processing time.


By using geographic corrdinates, you probably were generating a hugh 
raster which caused your computer to hang.


Kirk Schmidt

On 9/30/2021 3:03 PM, Maria Eugenia Gomez wrote:
> Hi,
> I am using QGIS 3.16.9 Hannover. I want to create a surface (with 
> kriging) from a list of points whose SRC is WGS84. They are in decimal 
> degrees covering a surface of 10km x 9km. I can see the points correctly-
>
> My problem comes with the "Ordinary Kriging" setup. I unchecked "block 
> kriging" and used the following options:
> quality measure: stand. dev.
> Logarithmic transf.
> variogram model: linear
> fit:nodes
> search range: local
> search directions: all directions
> number of points: max. number of points
>
> But when I have to fill "cell size", "maximum search distance, block 
> size.. etc", I do not understand the units and I think this is the 
> problem. Which type of units should I use? I tried to use decimal 
> degrees units but then the number of iterations was so high that my 
> computer hangs.
>
> Can somebody help me with this? I searched on the QGIS documentation 
> but it does not say anything about units.
> Thanks in advance,
> Maria
>
>
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user

-- 
Kirk Schmidt, MScF, BScF, RPF
General Manager
Nortek Resource Solutions Inc.
26 Church Road
Sutherlands River, NS
B0K 1W0
Tel (902) 922.3607
Email: kirk at nortekresources.com
Web: www.nortekresources.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20211001/9eae2972/attachment.html>