topic Re: Using Reclassify in Python in Python Questions

Using Reclassify in Python

SoratoMarques — Wed, 13 Sep 2023 13:42:55 GMT

Hi,

I have one raster and would like to transform all values between -0,9 - 0 like 1 value, and 0 - 0,9 like NoData.

How can I to this in python?

Thank´s

Re: Using Reclassify in Python

DanPatterson — Wed, 13 Sep 2023 19:15:36 GMT

Reclassify (Spatial Analyst)—ArcGIS Pro | Documentation

See the code examples for the spatial analyst extension.

Re: Using Reclassify in Python

HaydenWelch — Wed, 13 Sep 2023 19:34:29 GMT

Have you used the arcpy.ddd.Reclassify tool yet?

From the docs:

import arcpy # Set Environment arcpy.env = r"<PATH TO ENVIRONMENT>" # Set local variables inRaster = "landuse" field = "VALUE" remapString = "1 9;2 8;3 1;4 6;5 3;6 2;7 1" outRaster = "C:/output/reclass3d" # Execute Reclassify arcpy.ddd.Reclassify(inRaster, field, remapString, outRaster, "DATA")

In your case you would do something like this:

import arcpy arcpy.env = r"<PATH TO ENVIRONMENT>" remap = "-0.9 0 1" raster = r"<PATH TO RASTER>" field = "<RECLASS FIELDNAME>" out_raster = r"<PATH TO OUTPUT RASTER>" arcpy.ddd.Reclassify(raster, field, remap, out_raster, "NODATA")

The "NODATA" flag at the end will write any values outside the provided remap range with NoData instead of the original values, so in your case you only define the remap for the lower end and just don't map the values over 0

Re: Using Reclassify in Python

mody_buchbinder — Thu, 14 Sep 2023 12:12:22 GMT

If you want ESRI to set the classes for you using some good algorithms you can try Slice https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-analyst/slice.htm