Weighted Overlay

Overlays several rasters using a common measurement scale and weights each according to its importance.

Learn more about how Weighted Overlay works


Illustration

Weighted Overlay illustration

Usage tips

Command line and Scripting

Syntax

WeightedOverlay_sa (in_weighted_overlay_table, out_raster)
Parameter Explanation Datatype
Weighted overlay table (Required)

The weighted overlay table allows the calculation of a multiple criteria analysis between several rasters.

  • Raster — The raster of the criteria being weighted.

  • Influence — The influence of the raster compared to the other criteria as a percentage of 100.

  • Field — The field of the criteria raster to use for weighting.

  • Remap — The scaled weights for the criterion.

In addition to numerical values for the scaled weights in Remap, the following options are available:

  • RESTRICTED — Assigns the restricted value (the minimum value of the evaluation scale set, minus one) to cells in the output, regardless of whether other input rasters have a different scale value set for that cell.

  • NODATA — Assigns NoData to cells in the output, regardless of whether other input rasters have a different scale value set for that cell.

(Raster Layer Double Field Remap; Raster Layer Double Field Remap;...)
Output raster (Required)

The raster to be created.

Raster Dataset
Data types for geoprocessing tool parameters

Script Example

# WeightedOverlay_sample.py
# Description: 
#   Overlays several rasters using a common scale and weighing 
#   each according to its importance.
# Requirements: None
# Author: ESRI
# Date: Sept 6, 2005

# Import system modules
import arcgisscripting

# Create the Geoprocessor object
gp = arcgisscripting.create()

try:
    # Set local variables
    sInWOTable = "('C:\data\landuse' 65 'Value' (3 3; 4 4; 10 10;NODATA -1); _
         'C:\data\school' 35  'Value' (1 1; 4 4; 5 5; 8 8; 9 9; NODATA -1));1 10 1"
    sOutWOT = "C:/data/out_wot"

    # Check out Spatial Analyst extension license
    gp.CheckOutExtension("Spatial")

    # Process: WeightedOverlay
    gp.WeightedOverlay_sa(sInWOTable, sOutWOT)

except:
    # If an error occurred while running a tool, then print the messages.
    print gp.GetMessages()

Map Algebra syntax

Not Available


ArcObjects syntax

Not Available


See Also

  • Understanding overlay analysis