Python support
The Earth Engine Python client library is compatible with Python versions supported by Google Cloud. Support is updated annually following the Python point release schedule (PEP 602; Status of Python versions). Using unsupported Python versions may cause authentication failures, unexpected behavior, or failure of certain operations.
Install options
If you are using Google Colab, the latest version of the Earth Engine Python client library has already been installed (via pip). Try the following notebook to get started with Earth Engine and Colab:
If you don't use Colab, the Earth Engine client library can be manually installed and updated on your system using conda (recommended) or pip:
Package import
The Python API package is called ee
. It must be imported and initialized for
each new Python session and script:
import ee
Authentication and Initialization
Prior to using the Earth Engine Python client library, you need to authenticate and use the resultant credentials to initialize the Python client. Run:
ee.Authenticate()
This will select the best authentication mode for your environment, and prompt you to confirm access for your scripts. To initialize, you will need to provide a project that you own, or have permissions to use. This project will be used for running all Earth Engine operations:
ee.Initialize(project='my-project')
See the authentication guide for troubleshooting and to learn more about authentication modes and Cloud projects.
Hello world!
Here is a short script to test that you're all set for working with Earth Engine.
import ee ee.Authenticate() ee.Initialize(project='my-project') print(ee.String('Hello from the Earth Engine servers!').getInfo())
Syntax
Both the Python and JavaScript APIs access the same server-side functionality, but client-side expressions (learn more about client vs. server) can vary because of language syntax differences. The following table includes a list of the common syntax differences you'll encounter when working with the Python API relative to the JavaScript API.
Property | JavaScript | Python |
---|---|---|
Function definition |
function myFun(arg) { return arg; } var myFun = function(arg) { return arg; }; |
def my_fun(arg): return arg |
Anonymous function mapping |
var foo = col.map(function(arg) { return arg; }); |
foo = col.map(lambda arg: arg) |
Variable definition |
var myVar = 'var'; |
my_var = 'var' |
Logical operators |
var match = such.and(that); var match = such.or(that); var match = such.not(that); |
match = such.And(that) match = such.Or(that) match = such.Not(that) |
Multi-line method chain |
var foo = my.really() .reallyLong() .methodChain(); |
foo = (my.really() .reallyLong() .methodChain()) |
Dictionary keys |
var dic = {'key': value}; var dic = {key: value}; |
dic = {'key': value} |
Dictionary object access |
var value = dic.key; var value = dic['key']; |
value = dic['key'] |
Function argument definition |
// Positional arguments. var foo = fun(argX, argY, argZ); // Keyword arguments object. var foo = fun({y: argY}); |
# Positional arguments. foo = fun(arg_x, arg_y, arg_z) # Keyword arguments dictionary. foo = fun(**{'y': arg_y}) # Keyword arguments. foo = fun(x=arg_x, z=arg_z) |
Boolean |
var t = true; var f = false; |
t = True f = False |
Null values |
var na = null; |
na = None |
Comment |
// |
# |
Date objects
Define and manipulate client-side date objects with the
datetime
module. Include the module in your script:
import datetime
Convert ee.Date
to client-side date:
ee_date = ee.Date('2020-01-01') py_date = datetime.datetime.utcfromtimestamp(ee_date.getInfo()['value']/1000.0)
Convert client-side date to ee.Date:
py_date = datetime.datetime.utcnow() ee_date = ee.Date(py_date)
Exporting data
Exporting data with the Python API requires the use of the ee.batch
module, which provides an interface to the
Export
functions. Pass parameter arguments as you would with the JavaScript API, minding the
differences noted in the syntax table above. Export tasks must be
started by calling the start()
method on a defined task. Query a task's status by
calling the status()
method on it. The following example demonstrates exporting
an ee.Image
object.
Create an export task:
task = ee.batch.Export.image.toDrive(image=my_image, # an ee.Image object. region=my_geometry, # an ee.Geometry object. description='mock_export', folder='gdrive_folder', fileNamePrefix='mock_export', scale=1000, crs='EPSG:4326')
Start an export task:
task.start()
Check export task status:
task.status()
The result of task.status()
is a dictionary containing information such as the
state of the task and its ID.
{ 'state': 'READY', 'description': 'my_export_task', 'creation_timestamp_ms': 1647567508236, 'update_timestamp_ms': 1647567508236, 'start_timestamp_ms': 0, 'task_type': 'EXPORT_IMAGE', 'id': '56TVJIZABUMTD5CJ5YHTMYK4', 'name': 'projects/earthengine-legacy/operations/56TVJIZABUMTX5CJ5HHTMYK4' }
You can monitor task progress using the state
field. See the Processing
Environments page for a
list of state
values and more information on
task lifecycle.
Printing objects
Printing an Earth Engine object in Python prints the serialized request for the object, not the object itself. Refer to the Client vs. server page to understand the reason for this.
Call getInfo()
on Earth Engine objects to get the desired object from the server
to the client:
# Load a Landsat image. img = ee.Image('LANDSAT/LT05/C02/T1_L2/LT05_034033_20000913') # Print image object WITHOUT call to getInfo(); prints serialized request instructions. print(img) # Print image object WITH call to getInfo(); prints image metadata. print(img.getInfo())
getInfo()
is a synchronous operation, meaning execution of expressions
following the getInfo()
call are blocked until the result is returned to the client.
Additionally, requests for a lot of data or expensive computations can return an error and/or
hang. In general, the best practice is to
export your results,
and once complete, import them into a new script for further analysis.
UI objects
The Earth Engine ui
module is only available through the JavaScript API Code
Editor. Use third party libraries for UI elements in Python. Libraries such as
geemap,
Folium, and
ipyleaflet
provide interactive map display, while charting can be done with
Matplotlib,
Altair, or
seaborn, to name a few. See examples
in the
Earth Engine in Colab setup notebook for using geemap and Matplotlib.
Python in the Developer Guide
Python code is included throughout the Earth Engine Developer Guide. Where available,
code examples can be viewed by clicking on the "Colab (Python)" tab at the top of code blocks.
Guide pages may also include buttons at the top for running the page as a Colab notebook or
viewing on GitHub. Python code examples are intended to be run using
Google Colab. Interactive map and object exploration are
handled by the geemap
library. Both the Earth Engine Python client library and geemap
are preinstalled
in Colab.
Earth Engine setup
Running Python code requires that you import the Earth Engine library, authenticate, and initialize. The following commands are used in examples (see the Authentication and Initialization page for alternatives).
import ee ee.Authenticate() ee.Initialize(project='my-project')
Interactive exploration with geemap
The geemap
library is used
for displaying map tiles and printing rich representations of Earth Engine objects.
The library depends respectively on
ipyleaflet
and eerepr
for these features.
The geemap
library and its dependencies are preinstalled in Google Colab;
import it into each session.
import geemap.core as geemap
Geographic Earth Engine data classes, such as ee.Image
and
ee.FeatureCollection
, can be viewed using the geemap.Map
object.
First, define the map object. Then, add layers to it or alter its viewport.
# Initialize a map object. m = geemap.Map() # Define an example image. img = ee.Image.random() # Add the image to the map. m.add_layer(img, None, 'Random image') # Display the map (you can call the object directly if it is the final line). display(m)