To summarize: We have 28.5 million XY coordinates we would like to compare up to 6 raster values for, and prefer to look at those values in JMP.
We are exploring interpolation methods in ArcGIS for DEM creation and would like to compare the values resulting from those methods. We have 24 sites, and most have 6 rasters to compare. Not every site has every raster, though. The sites range from 0.5 million to 2 million cells, and the total cell count for all raster footprints is 28.5 million cells. What I would like to have is a table I can manipulate in JMP with the 28.5 million records and the 6 fields for elevation plus the following fields: X coordinates, Y coordinates, sitecode (2-4 letters), and ecoregion (2-4 letters).
Our usual process for looking at multiple values across coincident/overlapping rasters is to convert one raster to points (using Raster to Point), use Multivalue to Point to grab the other values, and export the resulting table to text. We do this site by site so that the sitecode field can be populated easily. We then concatenate all of the tables in JMP and do our analysis.
The rasters are stored separately, though some have been grouped into mosaic datasets within a geodatabase so I could explore my options.
The issues:
[I would like to note that we have capable computers with Xeon hexacore hyperthreaded processors and 32GB RAM, so hardware should not be excessively limiting. I'm not sure what the software can actually use, however. Also, I have limited Python experience, and no experience with programs other than ArcGIS. I would be open to exploring other software in the future, but am limited by time right now and think I should stick to Arc.]
أكثر...
We are exploring interpolation methods in ArcGIS for DEM creation and would like to compare the values resulting from those methods. We have 24 sites, and most have 6 rasters to compare. Not every site has every raster, though. The sites range from 0.5 million to 2 million cells, and the total cell count for all raster footprints is 28.5 million cells. What I would like to have is a table I can manipulate in JMP with the 28.5 million records and the 6 fields for elevation plus the following fields: X coordinates, Y coordinates, sitecode (2-4 letters), and ecoregion (2-4 letters).
Our usual process for looking at multiple values across coincident/overlapping rasters is to convert one raster to points (using Raster to Point), use Multivalue to Point to grab the other values, and export the resulting table to text. We do this site by site so that the sitecode field can be populated easily. We then concatenate all of the tables in JMP and do our analysis.
The rasters are stored separately, though some have been grouped into mosaic datasets within a geodatabase so I could explore my options.
The issues:
- Doing each site separately is very time consuming and could lead toerrors.
- Using a single point file seems like a good idea, but I'm not sure how to easily populate the sitecode if we do them all at once. Perhaps we can use the footprints of the mosaicraster dataset using a method similar to this.
- Using many different rasters will result in a different field and field name for values that actually belong in the same column (i.e., rasters sharing the same creation method should be in one column but would each have their own).
- Using a single shapefile for all the points as an input to Multi Value to Points took 18 hours to get to 5% complete with only 2 raster types as inputs (so approximately 24 rasters).
- Generating a point feature class in thegeodatabase took 43 minutes for one raster, where as exporting the sameraster to a point shapefile took 32 seconds, so working with thepoints in a geodatabase doesn't seem practical.
[I would like to note that we have capable computers with Xeon hexacore hyperthreaded processors and 32GB RAM, so hardware should not be excessively limiting. I'm not sure what the software can actually use, however. Also, I have limited Python experience, and no experience with programs other than ArcGIS. I would be open to exploring other software in the future, but am limited by time right now and think I should stick to Arc.]
أكثر...