Less Than Frequency (Spatial Analyst)
Summary
Evaluates on a cell-by-cell basis the number of times a set of rasters is less than another raster.
Illustration
 |
OutRas = LessThanFrequency(ValRas, [InRas1, InRas2, InRas3] |
Usage
-
An arbitrary number of rasters can be specified in the input rasters list.
-
If a cell location contains NoData on any of the input rasters, that location will be assigned NoData on the output.
-
The output raster is always of integer type.
Syntax
| Parameter | Explanation | Data Type |
in_value_raster |
For each cell location in the input value raster, the number of occurrences (frequency) where a raster in the input list has a lesser value is counted. | Raster Layer |
in_rasters [in_raster,...] |
The list of rasters that will be compared against the value raster. | Raster Layer |
Return Value
| Name | Explanation | Data Type |
| out_raster |
The output raster. For each cell in the output raster, the value represents the number of times that the corresponding cells in the list of rasters is less than the value raster. | Raster |
Code Sample
This example evaluates the number of times a set of input GRID rasters is less than another raster and outputs the result as an IMG raster.
import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outLTF = LessThanFrequency("cost", ["degs", "negs", "fourgrd"])
outLTF.save("C:/sapyexamples/output/outltf.img")
This example evaluates the number of times a set of input GRID rasters is less than another raster and outputs the result as an IMG raster.
# Name: LessThanFrequency_Ex_02.py
# Description: Evaluates the number of times a set of rasters is
# less than another raster
# Requirements: Spatial Analyst Extension
# Author: ESRI
# Import system modules
import arcpy
from arcpy import env
from arcpy.sa import *
# Set environment settings
env.workspace = "C:/sapyexamples/data"
# Set local variables
inValueRaster = "cost"
inRaster01 = "degs"
inRaster02 = "negs"
inRaster03 = "fourgrd"
# Check out the ArcGIS Spatial Analyst extension license
arcpy.CheckOutExtension("Spatial")
# Execute LessThanFrequency
outLTF = LessThanFrequency(inValueRaster, [inRaster01, inRaster02, inRaster03])
# Save the output
outLTF.save("C:/sapyexamples/output/outltf")