VARI

Zusammenfassung

Calculates the Visible Atmospherically Resistant Index (VARI) from a multiband raster object and returns a raster object with the index values.

Auswertung

Der Visible Atmospherically Resistant Index (VARI) ist ein Vegetationsindex. Er dient zur quantitativen Schätzung des Vegetationsanteils, der ausschließlich anhand des sichtbaren Anteils des Spektrums bestimmt wird.

VARI = (Green - Red) / (Green + Red – Blue)

For information about other multiband raster indexes, see the Band Arithmetic 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

VARI (raster, {red_band_id}, {green_band_id}, {blue_band_id})

Parameter	Erklärung	Datentyp
raster	The input raster.	Raster
red_band_id	The band ID of the red-edge band. The band ID index uses one-based indexing. (Der Standardwert ist 3)	Integer
green_band_id	The band ID of the green band. The ID index uses one-based indexing. (Der Standardwert ist 2)	Integer
blue_band_id	The band ID of the blue band. The ID index uses one-based indexing. (Der Standardwert ist 1)	Integer

Rückgabewert

Datentyp	Erklärung
Raster	The output raster with the VARI values.

Codebeispiel

VARI example

Calculates the Visible Atmospherically Resistant Index for a Landsat 8 image.

import arcpy

VARI_raster = arcpy.ia.VARI("Landsat8.tif",4,3,2)