Illegal subscript range: DEM_ARR.
Question:
I have been trying to create a new project with my DEM-Tiff-File. Unfortunately, this failed and I see one of the following errors:
- REVERSE: Subscript_index must be less than or equal to number of dimensions
- Illegal subscript range: DEM_ARR.
Answer:
There are several common reasons why a DEM might cause errors in RAMMS. Please check the following:
- Incorrect Coordinate System:
Your DEM may be using a geographic (spherical) coordinate system, where coordinates are in degrees (latitude/longitude). RAMMS requires DEMs to be in a projected coordinate system, such as UTM, where all units are in meters. Please reproject your DEM to UTM using a GIS tool like QGIS or ArcGIS. - DEM is not Elevation Data:
Some files that appear to be DEMs are actually hillshade images or visual map layers containing RGB color values instead of elevation (Z) values. RAMMS requires a true elevation raster, where pixel values represent ground elevation in meters. - Corrupt or Incompatible DEM Format:
Ensure that the DEM file is in a supported raster format (e.g., GeoTIFF) and not corrupted. You may also try re-exporting the DEM from your GIS software with clean settings.
Solution:
Verify your DEM’s coordinate system and data type, correct any issues as described above, and then attempt to create a new project in RAMMS with the corrected DEM.