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UnitConversion

Summary

Converts pixels from one unit to another. It supports conversion of distance, speed, and temperature.

Discussion

For more information about how this function works, see the Unit Conversion raster function.

The referenced raster dataset for the raster object is temporary. To make it permanent, you can call the raster object's save method.

Syntax

UnitConversion(raster, {from_unit}, {to_unit})

Parameter Explanation Data Type

raster

The input raster that will contain the converted units.

Raster

from_unit

The original unit type of the pixels.

  • MetersPerSecond—Meters per second

  • KilometersPerHour—Kilometers per hour

  • Knots—Knots

  • FeetPerSecond—Feet per second

  • MilesPerHour—Miles per hour

  • Celsius—Celsius

  • Fahrenheit—Fahrenheit

  • Kelvin—Kelvin

  • inches—Inches

  • Feet—Feet

  • Yards—Yards

  • Miles—Miles

  • NauticalMiles—Nautical miles

  • Millimeters—Millimeters

  • Centimeters—Centimeters

  • Meters—Meters

The default value is None.

String

to_unit

The converted unit type of the pixels.

  • MetersPerSecond—Meters per second

  • KilometersPerHour—Kilometers per hour

  • Knots—Knots

  • FeetPerSecond—Feet per second

  • MilesPerHour—Miles per hour

  • Celsius—Celsius

  • Fahrenheit—Fahrenheit

  • Kelvin—Kelvin

  • inches—Inches

  • Feet—Feet

  • Yards—Yards

  • Miles—Miles

  • NauticalMiles—Nautical miles

  • Millimeters—Millimeters

  • Centimeters—Centimeters

  • Meters—Meters

The default value is None.

String

Return value

Data Type Explanation

Raster

The output raster.

Code sample

UnitConversion example 1

This example calculates the input raster from meters per second to kilometers per hour.

from arcpy.sa import *
out_unit_raster = UnitConversion("wind_speed_meter_per_second.tif",
                                 "MetersPerSecond'", "KilometersPerHour")
out_unit_raster.save("C:/arcpyExamples/outputs/wind_speed_km_per_hour.tif")
UnitConversion example 2

This example calculates the input temperature raster from Celsius to Kelvin.

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

# Set the analysis environments
arcpy.env.workspace = "C:/arcpyExamples/data"

# Set the local variables
inRaster_File = "temperature_celcius.tif"
from_unit = 'Celsius'
to_unit = 'Kelvin'

# Run UnitConversion function
out_unit_raster = UnitConversion(inRaster_File, from_unit, to_unit)

# Save the output
out_unit_raster.save("C:/arcpyExamples/outputs/temperature_kelvin.tif")