[Qgis-user] kriging proble.

[Francois Chartier]

Hi,

i am resending this email as my previous email was too big.
I am trying to krige particle size at a given elevation for some borehole
information, see log sheet below
I have tried IDW which provide an interpolation over the defined extent.
  I would like to use kriging however, when it takes probably 20 to 30 min
to run using ordinary kriking, or a few min with simple kriging, and the
resulting interpolation in both cases are limited to approx 1000 m from the
data points.  I presume that this is due to the search radius of 1km. This
data set is only 700 points and shouldn't be that complicated to krig.  The
range of the interpolation also is out of range of the data points.  I am
not sure what I am doing wrong..



SEE log sheet below

Processing algorithm…

Algorithm 'Simple kriging' starting…

Input parameters:

{ 'BLOCK' : False, 'DBLOCK' : 100, 'FIELD' : 'ParticleSize', 'LOG' : False,
'POINTS' : 'C:/Users/Francois
Chartier/Documents/GeoModel/Intervals/130.gpkg|layername=130', 'PREDICTION'
: 'C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/5906333ae6674718b7180ff8a8166ac2/PREDICTION.sdat',
'SEARCH_DIRECTION' : 0, 'SEARCH_POINTS_ALL' : 0, 'SEARCH_POINTS_MAX' : 20,
'SEARCH_POINTS_MIN' : 16, 'SEARCH_RADIUS' : 1000, 'SEARCH_RANGE' : 0,
'TARGET_TEMPLATE' : None, 'TARGET_USER_FITS' : 0, 'TARGET_USER_SIZE' : 100,
'TARGET_USER_XMIN TARGET_USER_XMAX TARGET_USER_YMIN TARGET_USER_YMAX' :
'651700, 609200, 4862000, 4825700', 'TQUALITY' : 0, 'VARIANCE' :
'C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/30e93e365de34177a512d28cd8414007/VARIANCE.sdat',
'VAR_MAXDIST' : -1, 'VAR_MODEL' : 'a + b * x', 'VAR_NCLASSES' : 100,
'VAR_NSKIP' : 1 }


statistics_kriging "Simple Kriging" -TARGET_DEFINITION 0 -POINTS
"C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/9c11d34a631749ec91b9206a6a513f7c/POINTS.shp"
-FIELD "ParticleSize" -TQUALITY 0 -LOG false -BLOCK false -DBLOCK 100.0
-VAR_MAXDIST -1.0 -VAR_NCLASSES 100 -VAR_NSKIP 1 -VAR_MODEL "a + b * x"
-TARGET_USER_XMIN 609200.0 -TARGET_USER_XMAX 651700.0 -TARGET_USER_YMIN
4825700.0 -TARGET_USER_YMAX 4862000.0 -TARGET_USER_SIZE 100.0
-TARGET_USER_FITS 0 -SEARCH_RANGE 0 -SEARCH_RADIUS 1000.0
-SEARCH_POINTS_ALL 0 -SEARCH_POINTS_MIN 16 -SEARCH_POINTS_MAX 20
-SEARCH_DIRECTION 0 -PREDICTION "C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/5906333ae6674718b7180ff8a8166ac2/PREDICTION.sdat"
-VARIANCE "C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/30e93e365de34177a512d28cd8414007/VARIANCE.sdat"


C:\PROGRA~1\QGIS3~1.4\bin>set SAGA=C:/PROGRA~1/QGIS3~1.4/apps\saga-ltr


C:\PROGRA~1\QGIS3~1.4\bin>set
SAGA_MLB=C:/PROGRA~1/QGIS3~1.4/apps\saga-ltr\modules


C:\PROGRA~1\QGIS3~1.4\bin>PATH=C:\PROGRA~1\QGIS3~1.4\apps\qgis\bin;C:\PROGRA~1\QGIS3~1.4\apps\grass\grass-7.4.2\lib;C:\PROGRA~1\QGIS3~1.4\apps\grass\grass-7.4.2\bin;C:\PROGRA~1\QGIS3~1.4\apps\Python37;C:\PROGRA~1\QGIS3~1.4\apps\Python37\Scripts;C:\PROGRA~1\QGIS3~1.4\apps\qt5\bin;C:\PROGRA~1\QGIS3~1.4\apps\Python27\Scripts;C:\PROGRA~1\QGIS3~1.4\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32\WBem;C:\PROGRA~1\QGIS3~1.4\apps\Python37\lib\site-packages\pywin32_system32;C:\PROGRA~1\QGIS3~1.4\apps\Python37\lib\site-packages\numpy\.libs;C:/PROGRA~1/QGIS3~1.4/apps\saga-ltr;C:/PROGRA~1/QGIS3~1.4/apps\saga-ltr\modules


C:\PROGRA~1\QGIS3~1.4\bin>saga_cmd statistics_kriging "Simple Kriging"
-TARGET_DEFINITION 0 -POINTS "C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/9c11d34a631749ec91b9206a6a513f7c/POINTS.shp"
-FIELD "ParticleSize" -TQUALITY 0 -LOG false -BLOCK false -DBLOCK 100.0
-VAR_MAXDIST -1.0 -VAR_NCLASSES 100 -VAR_NSKIP 1 -VAR_MODEL "a + b * x"
-TARGET_USER_XMIN 609200.0 -TARGET_USER_XMAX 651700.0 -TARGET_USER_YMIN
4825700.0 -TARGET_USER_YMAX 4862000.0 -TARGET_USER_SIZE 100.0
-TARGET_USER_FITS 0 -SEARCH_RANGE 0 -SEARCH_RADIUS 1000.0
-SEARCH_POINTS_ALL 0 -SEARCH_POINTS_MIN 16 -SEARCH_POINTS_MAX 20
-SEARCH_DIRECTION 0 -PREDICTION "C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/5906333ae6674718b7180ff8a8166ac2/PREDICTION.sdat"
-VARIANCE "C:/Users/Francois
Chartier/AppData/Local/Temp/processing_ec36cad732be463eb755fc7f6e89232f/30e93e365de34177a512d28cd8414007/VARIANCE.sdat"

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SAGA Version: 2.3.2 (64 bit)


____________________________

library path: C:\PROGRA~1\QGIS3~1.4\apps\saga-ltr\modules\

library name: statistics_kriging

library : Kriging

tool : Simple Kriging

author : O.Conrad (c) 2015

processors : 4 [4]

____________________________



Parameters



Points: POINTS

Attribute: fid

Type of Quality Measure: standard deviation

Logarithmic Transformation: no

Block Kriging: no

Maximum Distance: -1.000000

Lag Distance Classes: 100

Skip: 1

Model: a + b * x

Target Grid System: user defined

Cellsize: 100.000000

Left: 609200.000000

Right: 651700.000000

Bottom: 4825700.000000

Top: 4862000.000000

Fit: nodes

Search Range: local

Maximum Search Distance: 1000.000000

Number of Points: maximum number of nearest points

Minimum: 16

Maximum: 20

Direction: all directions






a = 39510.6

b = 0.973903







Loading resulting layers

Algorithm 'Simple kriging' finished
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