[GIS] Reclassify variable in ModelBuilder

Question

I want to reclassify a raster (variable) in model builder in two classes. First class ist 0-treshold = NoData and second is treshold-max value = 1. It works fine if i use an existing raster file as input (where i can state and know the max value) but not for variables in ModelBuilder.

Any ideas how to do it in ModelBuilder, or with ArcPy?

EDIT:

Here is my edited model, but it's not running yet.

Answer 1

Try this:

Replace your reclassify step with the following steps:

• Use the Get Raster Properties tool to retrieve the maximum value from your flow accummulation raster.
• Use the Calculate Value tool and a python snippet to reclassify your flow accumulation raster.
• Set the Data Type of the Calculate Value tool to "Raster Layer"

• Define the following function in the code block

  def apply_threshold(flow_acc, max_flow,threshold, rcls_flow_path):
       rcls = arcpy.sa.Reclassify(flow_acc,"Value","0 {0} NODATA; {0} {1} 1".format(threshold,max_flow), "DATA")
       rcls.save(rcls_flow_path)
       return rcls_flow_path
  

The function defined above accepts a flow accummulation raster, max flow value, a threshold and an output path. Values 0 - threshold are reclassed to NODATA and values from threshold to max value are reclassed to 1.

See sample model below.

• Connect the reclassed flow accumulation to the rest of your model....