AI-generated Key Takeaways
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This function produces an image where each pixel represents the distance in meters to the nearest geometry within a collection.
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Distances are computed on a sphere, introducing a small error proportional to the latitude difference.
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Pixels outside of the specified searchRadius from a geometry will be masked out.
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The function takes an input FeatureCollection, a searchRadius in meters, and an optional maxError for reprojection.
Distances are computed on a sphere, so there is a small error proportional to the latitude difference between each pixel and the nearest geometry.
| Usage | Returns |
|---|---|
FeatureCollection.
distance
( searchRadius
, maxError
)
|
Image |
| Argument | Type | Details |
|---|---|---|
|
this:
features
|
FeatureCollection | Feature collection from which to get features used to compute pixel distances. |
searchRadius
|
Float, default: 100000 | Maximum distance in meters from each pixel to look for edges. Pixels will be masked unless there are edges within this distance. |
maxError
|
Float, default: 100 | Maximum reprojection error in meters, only used if the input polylines require reprojection. If '0' is provided, then this operation will fail if projection is required. |
Examples
Code Editor (JavaScript)
// FeatureCollection of power plants in Belgium. var fc = ee . FeatureCollection ( 'WRI/GPPD/power_plants' ) . filter ( 'country_lg == "Belgium"' ); // Generate an image of distance to nearest power plant. var distance = fc . distance ({ searchRadius : 50000 , maxError : 50 }); // Display the image and FeatureCollection on the map. Map . setCenter ( 4.56 , 50.78 , 7 ); Map . addLayer ( distance , { max : 50000 }, 'Distance to power plants' ); Map . addLayer ( fc , { color : 'red' }, 'Power plants' );
import ee import geemap.core as geemap
Colab (Python)
# FeatureCollection of power plants in Belgium. fc = ee . FeatureCollection ( 'WRI/GPPD/power_plants' ) . filter ( 'country_lg == "Belgium"' ) # Generate an image of distance to nearest power plant. distance = fc . distance ( searchRadius = 50000 , maxError = 50 ) # Display the image and FeatureCollection on the map. m = geemap . Map () m . set_center ( 4.56 , 50.78 , 7 ) m . add_layer ( distance , { 'max' : 50000 }, 'Distance to power plants' ) m . add_layer ( fc , { 'color' : 'red' }, 'Power plants' ) m
