topic Create points from slope raster? in ArcGIS Pro Questions

Create points from slope raster?

BrianTickle — Mon, 17 Jan 2022 12:58:23 GMT

Problem: identify locations of exposed cliffs and bluffs with a minimum slope angle. I've created a DSM using 1m lidar and have performed slope analysis. I'm interested in creating a point feature class that plots points for areas that contain certain slope characteristics. For example, the attached pic shows slope values 75 degrees or steeper. I'd like to perform a calculation that looks at the slope raster and assigns points to areas that are likely to contain cliffs that are, perhaps, a certain continuous length and minimum vertical relief. Put simply, I'm looking for a model that analyzes a dsm and says, 'here's a point that might have a cliff.' Using ArcGIS Pro 2.9.0

Re: Create points from slope raster?

DanPatterson — Mon, 17 Jan 2022 16:02:22 GMT

have you tried query your slope raster to identify slopes within your desired slope range, using the Con statement or SetNull

Setting values to NoData with Set Null—ArcGIS Pro | Documentation

OutRas = SetNull(SlopeRaster <= ??, InRas1)

then extract to points

Raster to Point (Conversion)—ArcGIS Pro | Documentation

Re: Create points from slope raster?

BrianTickle — Fri, 21 Jan 2022 17:09:38 GMT

That worked for isolating the slope range! Thanks. But do you know if there's a way extract the resulting raster to points without returning a point for every pixel? Ideally, I'd like to extract a single point for a certain "volume" of slope. By volume, I mean a certain count of contiguous pixels. So, if in the slope raster I have one section of the raster with 100 contiguous pixels and another section with only 99 contiguous pixels, I'd like to extract only 1 point to be placed somewhere in the 100 pixel area. Hopefully that makes sense.

Re: Create points from slope raster?

DanPatterson — Fri, 21 Jan 2022 18:03:06 GMT

not without converting to vector

raster zones to vector (eg raster to polygon)

Raster to Polygon (Conversion)—ArcGIS Pro | Documentation

You might need to run a MultipartToSinglePart tool on the above.

Then if you really need just a point in each polygon/raster zone, perhaps

Feature To Point (Data Management)—ArcGIS Pro | Documentation

you perhaps could run

Zonal Geometry (Spatial Analyst)—ArcGIS Pro | Documentation

with the centroid option but that runs the possibility to have to run a RegionGroup to make sure each zone has a unique value (ie you might have several spatially separated zones with the same class)

then convert to point and use those points to extract the values