Find the elevations of multiple points

Learn how to find elevation values for points along a path in New Zealand's South Island.

Prerequisites

Steps

Create a new app

1. Open a terminal and create a new folder for your project.

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   mkdir find-the-elevations-of-multiple-points
   cd find-the-elevations-of-multiple-points

2. Initialize a new Node.js project. This creates a package.json file.

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   npm init

3. Install the required packages.

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   npm install @esri/arcgis-rest-request @esri/arcgis-rest-elevation --save

4. Create a new JavaScript file named index.js.

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   touch index.js

Get an access token

Create a new API key credential with the correct privileges to get an access token.

1. Go to the Create an API key tutorial and create an API key with the following privilege(s):
   
   • Privileges:
     • Location services > Elevation service
2. Copy the API key access token to your clipboard when prompted.

Make a request

1. Open your index.js file and import the packages.

   index.js

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   import { ApiKeyManager } from "@esri/arcgis-rest-request";
   import { findElevationAtManyPoints } from "@esri/arcgis-rest-elevation";
   
   

2. Paste in your access token.

   index.js

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   import { ApiKeyManager } from "@esri/arcgis-rest-request";
   import { findElevationAtManyPoints } from "@esri/arcgis-rest-elevation";
   
   const accessToken = "YOUR_ACCESS_TOKEN";
   const authentication = ApiKeyManager.fromKey(accessToken);
   
   

3. Make a request to find the elevations of multiple points along New Zealand's South Island and print the results.

   index.js

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   import { ApiKeyManager } from "@esri/arcgis-rest-request";
   import { findElevationAtManyPoints } from "@esri/arcgis-rest-elevation";
   
   const accessToken = "YOUR_ACCESS_TOKEN";
   const authentication = ApiKeyManager.fromKey(accessToken);
   
   findElevationAtManyPoints({
     coordinates: [
       [1.2783, 51.1102], // Dover, UK
       [1.3507, 51.0883],
       [1.4206, 51.0524],
       [1.4939, 51.0162],
       [1.5978, 50.9827],
       [1.7302, 50.9387] // Calais, France
     ],
     authentication
   }).then((response) => {
     console.log(JSON.stringify(response, null, 2));
   });

4. Save the file, then run it from the terminal.

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   node index.js

You should now see the results printed in your console.

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{
  "result": {
    "points": [
      {
        "x": 1.2783,
        "y": 51.1102,
        "z": 85.4,
        "spatialReference": {
          "wkid": 4326,
          "vcsWkid": 105700
        }
      },
      {
        "x": 1.3507,
        "y": 51.0883,

What's next?

Learn how to use additional location services in these tutorials: