Correlation and Reclassifying Issues

Discussion created by coljacks on Jun 4, 2011
Latest reply on Jun 7, 2011 by coljacks

I'm having a few problems calculating the correlation of two grids within ArcInfo Workstation. When I preform the correlation I keep getting a Divide by Zero Error.

These are the steps I've taken so you can fully understand
1. I Convert two layers (Plant Types and Soil Type) to a Grid format using ArcGIS 9.3 Spatial Analyst
2. I reclassify one of the layers so I'm isolating one particular type of plant (The other values are given Nodata)
3. The reclassified layer is now used as a mask for the Extract by Mask function on the soil types layer. This will produce a soils grid of just the area occupied by that particular plant
4. The particular plant grid and the soils grid are now correlated within the Grid function of ArcInfo but everytime there is an error that states divide by zero is not possible.

If I reclassify the values as a zero instead of NoData in Step 2 the correlation will work but this doesn't focus the correlation on just the areas occupied by the plants but rather a neighborhood around them.
Also all cell sizes and extents were consistent throughout the analysis (set through the environments)

Any Ideas as to why this isn't working?