AI-generated Key Takeaways
-
The
evaluate
method asynchronously retrieves the value of an object from the server and passes it to a provided callback function. -
The
callback
argument is a function that is called when the server returns an answer, receiving either a success value or a failure error message. -
In the JavaScript example,
evaluate
is used to transfer a server-sideee.String
to the client for use in aui.Label
. -
The Python client library does not have an
evaluate
method foree.String
objects;ee.String.getInfo()
should be used instead.
Usage | Returns |
---|---|
String.evaluate(callback) |
Argument | Type | Details |
---|---|---|
this: computedobject | ComputedObject | The ComputedObject instance. |
callback | Function | A function of the form function(success, failure), called when the server returns an answer. If the request succeeded, the success argument contains the evaluated result. If the request failed, the failure argument will contains an error message. |
Examples
Code Editor (JavaScript)
/** * WARNING: this function transfers data from Earth Engine servers to the * client. Doing so can negatively affect request processing and client * performance. Server-side options should be used whenever possible. * Learn more about the distinction between server and client: * https://developers.google.com/earth-engine/guides/client_server */ // A server-side ee.String object fetched from a feature property. var stringServer = ee.Feature(null, {lc: 'grassland'}).getString('lc'); // Use evaluate to transfer server-side string to client for use in ui.Label. stringServer.evaluate(function(stringClient) { print('Client-side primitive data type', typeof stringClient); // string print('Client-side string', stringClient); // grassland print('Client-side string used in ui.Label', ui.Label('Land cover: ' + stringClient)); // Land cover: grassland });
import ee import geemap.core as geemap
Colab (Python)
# The Earth Engine Python client library does not have an evaluate method for # asynchronous evaluation of ee.String objects. # Use ee.String.getInfo() instead.