I need to calculate slope in percent gradient for points in a given feature class. My workflow is as follows:
1. Set up an .mxd with the desired feature class in a projected coordinate system and the the data frame in the same projected coordinate system (NAD83 UTM z10)
2. Import Terrrain: Slope degrees layer from AGOL, and project that on the fly.
3. Use the "Extract Values to Points" tool in Spatial analyst tools.
4. A new feature class is created with a field called RASTERVALU. Now here is where my questions begin. Is this value the slope in degrees?
5. Create a new field called "PCNT_SLP" and make it a double field type.
6. Populate the field with a calculation that converts degrees (RASTERVALU) to radians, calculate the tangents of the radians and then multiply by 100. The python formula I put together for the field calculator is:
math.tan( math.radians( !RASTERVALU! ) ) *100
Am I going about this correctly or am I way off?