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I'm using Grid (Moving average) to get mean values of Point attribute in a circle of 20 m radius.

What is determining the step distance / the output pixel size? I can't find it in the documentation. I would like to set I manually to for example 10 m. enter image description here

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    Very interesting subject. Me neither could find any information. Looking at one old link I came across, I feel GDAL creates a blank base grid of 256 x 256 (Line 1132-1136) unless specified by the user. If it is the case the step distance could be 1/256 * xrange or yrange... NB. I am not a programmer. – Kazuhito Feb 6 at 12:15
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    You can try with the optional parameters -outsize (in pixel/line count) and/or -txe -txy – JGH Feb 6 at 12:21
  • @JGH that is the answer. If you want to post it please do or I will. – BERA Feb 7 at 12:43
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    @BERA please go ahead, you have the proper numerical values to put in the answer. Great that it is working! – JGH Feb 7 at 13:22
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I dont know what is determining step distance if used in QGIS GUI but as commented it is possible to set it using the optional parameters -outsize, -txe and txy.

For example to get 10 m pixels I use command below in terminal:

gdal_grid -zfield datafield -a average:radius1=20:radius2=20:angle=0.0:min_points=0:nodata=0.0 -txe 626400 629800 -tye 6680000 6682000 -outsize 340 200 -ot Float32 -of GTiff D:/folder/someinputpointshapefile.shp D:/folder/OUTPUT.tif

(To calculate outsize:

(6682000-668000)/10=340
(629800-626400)/10=200

)

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