ee.Geometry.MultiLineString.dissolve

  • The dissolve method returns the geometric union of a geometry, effectively merging the components of Multi geometries like MultiLineStrings into a single, unified geometry.

  • It leaves single geometries unchanged, only impacting Multi geometries.

  • dissolve can be customized using optional parameters: maxError to control the tolerance for reprojection errors and proj to specify the projection for the union operation (defaults to spherical if unspecified).

 Returns the union of the geometry. This leaves single geometries untouched, and unions multi geometries.

UsageReturns
MultiLineString.dissolve(maxError, proj)Geometry
ArgumentTypeDetails
this: geometryGeometryThe geometry to union.
maxErrorErrorMargin, default: nullThe maximum amount of error tolerated when performing any necessary reprojection.
projProjection, default: nullIf specified, the union will be performed in this projection. Otherwise it will be performed in a spherical coordinate system.

Examples

Code Editor (JavaScript)

// Define a MultiLineString object.
var multiLineString = ee.Geometry.MultiLineString(
   [[[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],
    [[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]]]);

// Apply the dissolve method to the MultiLineString object.
var multiLineStringDissolve = multiLineString.dissolve({'maxError': 1});

// Print the result to the console.
print('multiLineString.dissolve(...) =', multiLineStringDissolve);

// Display relevant geometries on the map.
Map.setCenter(-122.085, 37.422, 15);
Map.addLayer(multiLineString,
             {'color': 'black'},
             'Geometry [black]: multiLineString');
Map.addLayer(multiLineStringDissolve,
             {'color': 'red'},
             'Result [red]: multiLineString.dissolve');

Python setup

See the Python Environment page for information on the Python API and using geemap for interactive development.

import ee
import geemap.core as geemap

Colab (Python)

# Define a MultiLineString object.
multilinestring = ee.Geometry.MultiLineString([
    [[-122.088, 37.418], [-122.086, 37.422], [-122.082, 37.418]],
    [[-122.087, 37.416], [-122.083, 37.416], [-122.082, 37.419]],
])

# Apply the dissolve method to the MultiLineString object.
multilinestring_dissolve = multilinestring.dissolve(maxError=1)

# Print the result.
display('multilinestring.dissolve(...) =', multilinestring_dissolve)

# Display relevant geometries on the map.
m = geemap.Map()
m.set_center(-122.085, 37.422, 15)
m.add_layer(
    multilinestring, {'color': 'black'}, 'Geometry [black]: multilinestring'
)
m.add_layer(
    multilinestring_dissolve,
    {'color': 'red'},
    'Result [red]: multilinestring.dissolve',
)
m