Lowest Position (Spatial Analyst)

Summary

Determines on a cell-by-cell basis the position of the raster with the minimum value in a set of rasters.

Usage

• An arbitrary number of rasters can be specified in the input rasters list.

• The order of the input rasters is relevant for this tool.

• When a multiband raster is specified as one of the Input rasters or constant values (in_rasters_or_constants in Python), all the bands will be used.

To process a selection of bands from a multiband raster, first create a raster dataset composed of those particular bands using the Composite Bands tool; then use the result in the list of Input rasters or constant values (in_rasters_or_constants in Python).

• 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.

• If two or more input rasters contain the minimum value for a particular cell location, the position of the first one encountered is returned on the output raster.

• See Analysis environments and Spatial Analyst for additional details on the geoprocessing environments that apply to this tool.

Syntax

`LowestPosition(in_rasters_or_constants)`
 Parameter Explanation Data Type in_rasters_or_constants[in_raster_or_constant,...] The list of input rasters for which the position of the input with the lowest value will be determined.A number can be used as an input; however, the cell size and extent must first be set in the environment. Raster Layer; Constant

Return Value

 Name Explanation Data Type out_raster The output raster.For each cell in the output raster, the value represents the position of the raster with the lowest value. Raster

Code sample

LowestPosition example 1 (Python window)

This example evaluates several input rasters and returns as an output value the position in the list of the raster with the minimum value.

``````import arcpy
from arcpy import env
from arcpy.sa import *
env.workspace = "C:/sapyexamples/data"
outLowestPosition = LowestPosition(["degs", "negs", "fourgrd"])
outLowestPosition.save("C:/sapyexamples/output/outlp.tif")``````
LowestPosition example 2 (stand-alone script)

This example evaluates several input rasters and returns as an output value the position in the list of the raster with the minimum value.

``````# Name: LowestPosition_Ex_02.py
# Description: Determines the position of a raster with the minimum
#              value in a set of rasters
# Requirements: Spatial Analyst Extension

# Import system modules
import arcpy
from arcpy import env
from arcpy.sa import *

# Set environment settings
env.workspace = "C:/sapyexamples/data"

# Set local variables
inRaster01 = "degs"
inRaster02 = "negs"
inRaster03 = "fourgrd"

# Execute LowestPosition
outLowestPosition = LowestPosition([inRaster01, inRaster02, inRaster03])

# Save the output
outLowestPosition.save("C:/sapyexamples/output/outlp")``````

Licensing information

• Basic: Requires Spatial Analyst
• Standard: Requires Spatial Analyst