Gridding problem when using IMPORT_ASCII for elevation grid
pernille
Global Mapper User
Hi
I am trying to import a number of ascii elevation grids and store them in a map catalog.
When I import each grid manually, I get a very tight grid (no interpolation over small gaps) if I set the Elevation Grid "No Data" Distance Criteria to Tight (0.5).
When using IMPORT_ASCII (with NO_DATA_DIST_MULT="0.50") the resulting grid is interpolating across small gaps in the data. I also tried to load the grid manually, save the workspace, and copying the code from the workspace file to my script, but I still get the same result when running the script.
Manual_import.PNGScript_import.PNG
My code looks like this (as copied from the workspace file):
IMPORT_ASCII FILENAME="%FNAME_W_DIR%" \
PROJ_NAME="UTM_ZONE30_WGS84" TYPE="ELEVATION" COORD_DELIM="AUTO" COORD_FORMAT="DECIMAL" \
COORD_ORDER="X_FIRST" INC_COORD_LINE_ATTRS="NO" COL_HEADERS="NO" INC_ELEV_COORDS="YES" \
CREATE_AREAS_FROM_LINES="NO" GRID_FILL_TO_BOUNDS="NO" GRID_IGNORE_ZERO="NO" NO_DATA_DIST_MULT="0.050" \
SPATIAL_RES="0.50000000,0.50000000" SKIP_COLUMNS="0" SKIP_ROWS="0" LINE_TYPE="Unclassified Line Feature" \
LABEL_FIELD_FORCE_OVERWRITE="NO" SAMPLING_METHOD="BILINEAR" CLIP_COLLAR="NONE" ELEV_UNITS="METERS"
Any help is appreciated.
Thanks
I am trying to import a number of ascii elevation grids and store them in a map catalog.
When I import each grid manually, I get a very tight grid (no interpolation over small gaps) if I set the Elevation Grid "No Data" Distance Criteria to Tight (0.5).
When using IMPORT_ASCII (with NO_DATA_DIST_MULT="0.50") the resulting grid is interpolating across small gaps in the data. I also tried to load the grid manually, save the workspace, and copying the code from the workspace file to my script, but I still get the same result when running the script.
Manual_import.PNGScript_import.PNG
My code looks like this (as copied from the workspace file):
IMPORT_ASCII FILENAME="%FNAME_W_DIR%" \
PROJ_NAME="UTM_ZONE30_WGS84" TYPE="ELEVATION" COORD_DELIM="AUTO" COORD_FORMAT="DECIMAL" \
COORD_ORDER="X_FIRST" INC_COORD_LINE_ATTRS="NO" COL_HEADERS="NO" INC_ELEV_COORDS="YES" \
CREATE_AREAS_FROM_LINES="NO" GRID_FILL_TO_BOUNDS="NO" GRID_IGNORE_ZERO="NO" NO_DATA_DIST_MULT="0.050" \
SPATIAL_RES="0.50000000,0.50000000" SKIP_COLUMNS="0" SKIP_ROWS="0" LINE_TYPE="Unclassified Line Feature" \
LABEL_FIELD_FORCE_OVERWRITE="NO" SAMPLING_METHOD="BILINEAR" CLIP_COLLAR="NONE" ELEV_UNITS="METERS"
Any help is appreciated.
Thanks
Comments
-
In case anyone else is having the same problem, I can add that the issue is in the EXPORT_ELEVATION command, not the import as I thought. Adding FILL_GAPS=NO to the EXPORT_ELEVATION command does the trick.
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