2

I have point data, where one point represents one 1 storm water outfall, looks like this:

enter image description here

(point data is across all of Long Island, New York).

I am having a bit of difficulty finding the best tool to create a raster density map. Essentially I want to use a density layer in a weighted overlay model (an area with high density of storm water outfalls would be less suitable...). I do not think I need to use Hot Spot Analysis because I am only interested in high v low density and not if they are actually statistically different from each other. I also have tried point density tool but I am having trouble figuring out the inputs (like radius length and cell size, etc).

0

2 Answers 2

4

This may be easier if you think of it in separate steps: first calculate the quantitative density, then reclassify that result into "high" and "low."

The Point Density tool inputs will be:

  • Input point features: your outfall points
  • Population field: Use NONE for this, because each point is being counted once. (If a point could represent multiple instances, e.g. if points represented people in a household, then this would be where to select the relevant count field. That doesn't apply here.)
  • Output raster: location for the output raster
  • Output cell size: This is optional, but will let you control the cell size of the output raster. The smaller the cell, the more refined the results, but the bigger the raster file.
  • Neighborhood: This value indicates how large of a neighborhood the tool will search for points. For example, a circle neighborhood of 5 meters (radius 5, units "Map" [assuming your map is in meters, here]), the tool will count all points that fall within a 5 meter radius circle around each cell.

Once you've got that, you can either use symbology to simply visualize the values as high/low, or you can run it through the Reclassify tool to get a raster of high/low data.

0

I think Point Density makes the most sense. I'd set the population field to "NONE" since you seem to want each point to count as one. The output will be a raster.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.