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I'm using QGIS and trying to create a DEM using this tutorial: https://www.youtube.com/watch?v=aJm9lewzooU I'm getting error messages when trying to run "natural neighbor" with my file of coordinates. I pasted the error log below, as well as the screenshot for the settings I used. Do you know what is causing this error? enter image description here

QGIS version: 3.16.1-Hannover
QGIS code revision: b381a90dca[![enter image description here][2]][2]
Qt version: 5.11.2
GDAL version: 3.1.4
GEOS version: 3.8.1-CAPI-1.13.3
PROJ version: Rel. 6.3.2, May 1st, 2020
Processing algorithm…
Algorithm 'Natural neighbour' starting…
Input parameters:
{ 'FIELD' : 'altitude (m)', 'METHOD' : 1, 'SHAPES' : 'delimitedtext://file:///C:/Users/EVG/Desktop/latlong.csv?type=csv&maxFields=10000&detectTypes=yes&xField=longitude&yField=latitude&crs=EPSG:26915&spatialIndex=no&subsetIndex=no&watchFile=no', 'TARGET_OUT_GRID' : 'TEMPORARY_OUTPUT', 'TARGET_TEMPLATE' : None, 'TARGET_USER_FITS' : 0, 'TARGET_USER_SIZE' : 0.005, 'TARGET_USER_XMIN TARGET_USER_XMAX TARGET_USER_YMIN TARGET_USER_YMAX' : '-93.137700000,-93.137400000,45.008800000,45.009000000 [EPSG:26915]', 'WEIGHT' : 0 }

grid_gridding "Natural Neighbour" -TARGET_DEFINITION 0 -SHAPES "C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/d04b7f8a78374cd7b19d97efc90135ce/SHAPES.shp" -FIELD "altitude (m)" -METHOD 1 -TARGET_USER_XMIN -93.1377 -TARGET_USER_XMAX -93.1374 -TARGET_USER_YMIN 45.0088 -TARGET_USER_YMAX 45.009 -TARGET_USER_SIZE 0.005 -TARGET_USER_FITS 0 -WEIGHT 0.0 -TARGET_OUT_GRID "C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/3c02fc10349c4e929b80d64fd7598377/TARGET_OUT_GRID.sdat"

C:\Users\EVG\Documents>set SAGA=C:/PROGRA~1/QGIS3~1.16/apps\saga-ltr

C:\Users\EVG\Documents>set SAGA_MLB=C:/PROGRA~1/QGIS3~1.16/apps\saga-ltr\modules

C:\Users\EVG\Documents>PATH=C:\PROGRA~1\QGIS3~1.16\apps\qgis\bin;C:\PROGRA~1\QGIS3~1.16\apps\Python37;C:\PROGRA~1\QGIS3~1.16\apps\Python37\Scripts;C:\PROGRA~1\QGIS3~1.16\apps\qt5\bin;C:\PROGRA~1\QGIS3~1.16\bin;C:\Windows\system32;C:\Windows;C:\Windows\system32\WBem;C:\PROGRA~1\QGIS3~1.16\apps\Python37\lib\site-packages\pywin32_system32;C:\PROGRA~1\QGIS3~1.16\apps\Python37\lib\site-packages\numpy\.libs;C:/PROGRA~1/QGIS3~1.16/apps\saga-ltr;C:/PROGRA~1/QGIS3~1.16/apps\saga-ltr\modules

C:\Users\EVG\Documents>call saga_cmd grid_gridding "Natural Neighbour" -TARGET_DEFINITION 0 -SHAPES "C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/d04b7f8a78374cd7b19d97efc90135ce/SHAPES.shp" -FIELD "altitude (m)" -METHOD 1 -TARGET_USER_XMIN -93.1377 -TARGET_USER_XMAX -93.1374 -TARGET_USER_YMIN 45.0088 -TARGET_USER_YMAX 45.009 -TARGET_USER_SIZE 0.005 -TARGET_USER_FITS 0 -WEIGHT 0.0 -TARGET_OUT_GRID "C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/3c02fc10349c4e929b80d64fd7598377/TARGET_OUT_GRID.sdat"
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SAGA Version: 2.3.2 (64 bit)

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library path: C:\PROGRA~1\QGIS3~1.16\apps\saga-ltr\modules\
library name: grid_gridding
library : Gridding
tool : Natural Neighbour
author : O.Conrad (c) 2008
processors : 8 [8]
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Load shapes: C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/d04b7f8a78374cd7b19d97efc90135ce/SHAPES.shp...




Parameters


Points: SHAPES
Attribute: type
Target Grid System: user defined
Cellsize: 0.005000
Left: -93.137400
Right: -93.137400
Bottom: 45.009000
Top: 45.009000
Fit: nodes
Method: Sibson
Minimum Weight: 0.000000



Save grid: C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/3c02fc10349c4e929b80d64fd7598377/TARGET_OUT_GRID.sdat...



C:\Users\EVG\Documents>exit
Execution completed in 6.89 seconds
Results:
{'TARGET_OUT_GRID': 'C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/3c02fc10349c4e929b80d64fd7598377/TARGET_OUT_GRID.sdat'}

Loading resulting layers
The following layers were not correctly generated.
• C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/296776b11bdb4764bdd1bbc3ab300d77/TARGET_OUT_GRID.sdat
You can check the 'Log Messages Panel' in QGIS main window to find more information about the execution of the algorithm.
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  • 1
    If I read right the parameters from the log TARGET_USER_XMIN -93.1377 -TARGET_USER_XMAX -93.1374 -TARGET_USER_YMIN 45.0088 -TARGET_USER_YMAX 45.009 -TARGET_USER_SIZE 0.005 you are trying to create an output that is smaller than one pixel.
    – user30184
    Commented Jan 22, 2021 at 20:05
  • Is "cellsize" the pixel size? I had it set to 1.
    – DanG
    Commented Jan 22, 2021 at 20:18

1 Answer 1

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The output extend you defined is quite weird:

'TARGET_USER_XMIN TARGET_USER_XMAX TARGET_USER_YMIN TARGET_USER_YMAX' : '-93.137700000,-93.137400000,45.008800000,45.009000000 [EPSG:26915]'

You use EPSG:26915 (NAD83 / UTM zone 15N), but your coordinates seem to be in EPSG:4326. The coordinates -93.137700000,45.008800000 in EPSG:26915 are located somewhere in the Pacific, several hundred km west of the Galapagos islands.

If I'm not mistaken, you are interested in an area around Minneapolis, however. This corresponds to your coordinates if they are interpreted in EPSG:4326. -93.137700000,45.008800000, this place here - this is the southwestern corner (x_min, y_min) of your extent, right? However, if I have a look at the north eastern corner of your extent (interpreting the coordinate values in EPSG:4326), it is just about 20 meters away. So something is wrong anyway with these coordinates.

The coordinates -93.137700000,45.008800000 in EPSG:26915 correspond to -0.0008 degrees N, -97.4883 degrees W in EPSG:4326, this point here out in the ocean. You have defined this as the corner in the SW of your extent (and similarly the other coordinates).

Do never interpret coordinates from one CRS with another one: they have to be re-calculated (transformed) between different CRS. You should re-define your extend in the CRS your layer is.

See details here to understand why your coordinates are somewhere out in the Pacific: https://gis.stackexchange.com/a/383437/88814

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  • You're right, the target area is in Minneapolis. I set the CRS to 4326 but I am still getting errors. Loading resulting layers The following layers were not correctly generated. • C:/Users/EVG/AppData/Local/Temp/processing_cqmvma/30d2973bfbef45be986fce47f197993b/TARGET_OUT_GRID.sdat
    – DanG
    Commented Jan 24, 2021 at 23:23
  • This message only tells you that it could not generate an output, but not the reason why. Can you provide the data you were using - that would be easier to find the error.
    – Babel
    Commented Jan 25, 2021 at 7:44

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