Class ElevationSampler

ElevationSampler

Allows for the sampling of elevations at particular locations.The example below shows how you can use this class to determine the highest point along the route from Denver to Grand Junction in Colorado, plot it on a map, and save the map to Google Drive.

// Get directions from Denver to Grand Junction.
var directions = Maps.newDirectionFinder()
    .setOrigin('Denver, CO')
    .setDestination('Grand Junction, CO')
    .setMode(Maps.DirectionFinder.Mode.DRIVING)
    .getDirections();
var route = directions.routes[0];

// Get elevation samples along the route.
var numberOfSamples = 30;
var response = Maps.newElevationSampler()
    .samplePath(route.overview_polyline.points, numberOfSamples)

// Determine highest point.
var maxElevation = Number.MIN_VALUE;
var highestPoint = null;
for (var i = 0; i < response.results.length; i++) {
  var sample = response.results[i];
  if (sample.elevation > maxElevation) {
    maxElevation = sample.elevation;
    highestPoint = sample.location;
  }
}

// Add the path and marker to a map.
var map = Maps.newStaticMap()
    .addPath(route.overview_polyline.points)
    .addMarker(highestPoint.lat, highestPoint.lng);

// Save the map to your drive
DocsList.createFile(Utilities.newBlob(map.getMapImage(), 'image/png', 'map.png'));

See also

Methods

Method Return type Brief description
sampleLocation(latitude, longitude)
Object Returns elevation data for a single point (lat/lng).
sampleLocations(points)
Object Returns elevation data for a series of points (lat/lng).
sampleLocations(encodedPolyline)
Object Returns elevation data for the points in an encoded polyline.
samplePath(points, numSamples)
Object Returns elevation data for a number of samples along a line, defined using a series of points.
samplePath(encodedPolyline, numSamples)
Object Returns elevation data for a number of samples along a line, defined using an encoded polyline.

Detailed documentation

sampleLocation(latitude, longitude)

Returns elevation data for a single point (lat/lng).

// Gets the elevation of Times Square using a point.
var data = Maps.newElevationSampler().sampleLocation(40.759011, -73.984472);
Logger.log(data.results[0].elevation);

Parameters

Name Type Description
latitude
Number the latitude of the point to sample
longitude
Number the longitude of the point to sample

Return

Object — a JSON Object containing the elevation data, as described here

sampleLocations(points)

Returns elevation data for a series of points (lat/lng).

// Gets the elevation of Times Square and Central Park using points.
var data = Maps.newElevationSampler().sampleLocations([
    // Times Square
    40.759011, -73.984472,
    // Central Park
    40.777052, -73.975464
]);
Logger.log('Times Square: ' + data.results[0].elevation);
Logger.log('Central Park: ' + data.results[1].elevation);

Parameters

Name Type Description
points
Number[] an array of latitude/longitude pairs

Return

Object — a JSON Object containing the elevation data, as described here

sampleLocations(encodedPolyline)

Returns elevation data for the points in an encoded polyline.

// Gets the elevation of Times Square and Central Park using a polyline.
var data = Maps.newElevationSampler().sampleLocations('yvwwF|aqbMwoBiw@');
Logger.log('Times Square: ' + data.results[0].elevation);
Logger.log('Central Park: ' + data.results[1].elevation);

Parameters

Name Type Description
encodedPolyline
String an encoded polyline of points to sample

Return

Object — a JSON Object containing the elevation data, as described here

samplePath(points, numSamples)

Returns elevation data for a number of samples along a line, defined using a series of points.

// Gets the elevation of five points between Times Square and Central Park.
var data = Maps.newElevationSampler().samplePath([
    // Times Square
    40.759011, -73.984472,
    // Central Park
    40.777052, -73.975464
], 5);
for (var i = 0; i < data.results.length; i++) {
  Logger.log(data.results[i].elevation);
}

Parameters

Name Type Description
points
Number[] an array of latitude/longitude pairs defining a path to sample over
numSamples
Integer the number of points to sample along the path of points

Return

Object — a JSON Object containing the elevation data, as described here

samplePath(encodedPolyline, numSamples)

Returns elevation data for a number of samples along a line, defined using an encoded polyline.

// Gets the elevation of five points between Times Square and Central Park.
var data = Maps.newElevationSampler().samplePath('yvwwF|aqbMwoBiw@', 5);
for (var i = 0; i < data.results.length; i++) {
  Logger.log(data.results[i].elevation);
}

Parameters

Name Type Description
encodedPolyline
String an encoded polyline of points defining a path to sample over
numSamples
Integer the number of points to sample along the path of points

Return

Object — a JSON Object containing the elevation data, as described here