Synthèse
Creates a raster object of a grayscale 3D representation of a surface by considering the illumination source location and shadows.
Discussion
For more information about how this function works, see the Hillshade 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.
Syntaxe
Hillshade (dem, {azimuth}, {altitude}, {z_factor}, {slope_type}, {ps_power}, {psz_factor}, {remove_edge_effect}, {hillshade_type})
Paramètre | Explication | Type de données |
dem | The input elevation raster. | Raster |
azimuth | Azimuth is the sun's relative position along the horizon (in degrees). This position is indicated by the angle of the sun measured clockwise from due north. An azimuth of 0 degrees indicates north, east is 90 degrees, south is 180 degrees, and west is 270 degrees. This parameter is only valid when the hillshade_type argument is set to TRADITIONAL. The default is 315 degrees, which is from the northwest. (La valeur par défaut est 315) | Double |
altitude | Altitude is the sun's angle of elevation above the horizon and ranges from 0 to 90 degrees. A value of 0 degrees indicates that the sun is on the horizon, that is, on the same horizontal plane as the frame of reference. A value of 90 degrees indicates that the sun is directly overhead. This parameter is only valid when the hillshade_type argument is set to TRADITIONAL. (La valeur par défaut est 45) | Double |
z_factor | The z-factor is a scaling factor used to convert the elevation values for two purposes:
If the x,y units and z units are in the same units of measure, the z-factor should be set to 1. The z-values of the input surface are multiplied by the z-factor when calculating the final output surface. (La valeur par défaut est 1) | Double |
slope_type | The inclination of slope can be output as either a value in degrees, or percent rise. Specify one of the following: DEGREE, PERCENTRISE, or SCALED. For more information, see Slope function. | Integer |
ps_power | Accounts for the altitude changes (or scale) as the viewer zooms in and out on the map display. It is the exponent applied to the pixel size term in the equation that controls the rate at which the z-factor changes to avoid significant loss of relief. This parameter is only valid when the slope_type is SCALED. (La valeur par défaut est 0.664) | Double |
psz_factor | Accounts for changes in scale as the viewer zooms in and out on the map display. The value controls the rate at which the z-factor changes. This parameter is only valid when the slope_type is SCALED. (La valeur par défaut est 0.024) | Double |
remove_edge_effect |
Using this option will avoid any resampling artifacts that may occur along the edges of a raster. The output pixels along the edge of a raster or beside pixels without a value will be populated with NoData; therefore, it is recommended that this option be used only when there are other rasters with overlapping pixels available. When overlapping pixels are available, these areas of NoData will display the overlapping pixel values instead of being blank.
(La valeur par défaut est False) | Boolean |
hillshade_type | Controls the illumination source for the hillshade.
(La valeur par défaut est 0) | Integer |
Type de données | Explication |
Raster | The output raster. |
Exemple de code
This example calculates the hillshade for a given elevation.
from arcpy.ia import *
out_hillshade_raster = Hillshade("elevation.tif", 180, 75, 0.3048)
out_hillshade_raster.save("C:/arcpyExamples/outputs/hillshade.tif")
This example calculates the hillshade for a given elevation.
# Import the system modules
import arcpy
from arcpy.ia import *
# Set the analysis environments
arcpy.env.workspace = "C:/arcpyExamples/data"
# Set the local variables
in_dem = "elevation.tif"
# Execute the Hillshade function
out_hillshade_raster = Hillshade(in_dem, 180, 75, 0.3048)
# Save the output
out_hillshade_raster.save("C:/arcpyExamples/outputs/hillshade.tif")
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