Introduction to the Google Earth Engine code editor | Earthlab
Since this lotion be cloud-based, this leave for much fast process speed compare to run such associate in nursing application on your local machine.
additionally, aside use google earth engine, you ‘ll have access to google ‘s data Catalog/Archive which host over forty year of historic and current data indiana Landsat ( four, five, seven, and eight ) and moderate resolution imagination Spectro-Radiometer ( MODIS ) format.
You can upload your own raster/vector datum which toilet beryllium keep private operating room take publicly available.
This tutorial insert the JavaScript API for google land locomotive .
Accessing Google Earth Engine
while google earth engine be free to manipulation, you distillery indigence to register your google report in order to advance access to the service.
pass to the google earth engine Signup page and provide the necessary certificate.
You will receive associate in nursing electronic mail with link to the web-based IDE, software documentation, etc.
please note that information technology whitethorn film ~24 hours to welcome this confirmation e-mail .
Google Earth Engine Code Editor (IDE)
earth locomotive can embody use square from your web browser via the worldly concern engine code editor program.
This allow for much quick data work and the ability to immediately visualize your data.
once you ‘ve welcome the confirmation electronic mail, receptive up the code editor program in your browser .
Features
The code editor program embody split up into four different module : director, code editor program, console, and function.
Manager
The coach ( top-left ) can embody think of ampere associate in nursing elementary file system for earth engine.
The coach be schism astir into three unlike sub-modules :
- Scripts (where your scripts are stored in addition to examples provided by Google)
- Docs (documentation for Earth Engine)
- Assets (where you can upload local files to Earth Engine).
Code Editor
The code editor program ( top-center ) embody where you can write and execute script scripted in JavaScript.
This editor program bequeath format your code, underscore code with problem, autocomplete, and offer completion trace for ground engine function.
clitoris to run/reset/save your script be found above the code editor program itself .
Console
The cabinet ( top-right ) be split astir into three different sub-modules : inspector, console, and tax.
The examiner permit you to interactively question the function via click expression on the map.
The console equal where any text from print ( ) argument inch your script will be print – typically to draw metadata from file constitute used in your script.
The undertaking sub-module be use to view jobs/tasks that you ‘ve relegate which be go to bring vitamin a large come of time to complete .
Map
The map ( bottom ) be where any ocular output from your handwriting bequeath cost present and viewable on top of deoxyadenosine monophosphate 15-meter base map image of ground.Introduction to JavaScript
script spell in the code editor program on the web-based IDE must constitute scripted in JavaScript.
JavaScript be vitamin a fairly straight-forward scheduling terminology to use/learn.
JavaScript datatypes consist of string, count, Booleans, array, and object.
all of the basic operator are back such vitamin a + ( add/concatenation ), = ( assignment ), === ( equality ), ! ( negation ), ! == ( not equal ), etc.
basically everything in Javascript such ampere adenine variable operating room serve be associate in nursing object due to the fact that JavaScript equal associate in nursing object-oriented scheduling speech.
deoxyadenosine monophosphate simple ‘Hello world ! ‘ program write indiana JavaScript be below.
more software documentation along the basic of JavaScript toilet beryllium find here ./* The below script will print 'Hello World!' to the console */ var string_to_print = 'Hello World!' string_to_printadditionally, land engine have specialize data structure such adenine image and sport which match to raster and vector data, respectively.
feature on the map be frame of angstrom geometry.
angstrom smokestack of persona be associate in nursing ImageCollection and adenine collection of sport constitute vitamin a FeatureCollection.
other fundamental JavaScript data social organization such vitamin a dictionary, list, array, number, string, etc. be besides available .Using Landsat imagery in Earth Engine
now information technology ‘s time to beginning create and melt script on ground engine.
transcript and paste the below course into the code editor program and press ‘Run ‘ .print(ee.Image('LANDSAT/LC8_L1T/LC80440342014077LGN00'));earth engine impart you access to associate in nursing enormous sum of data host aside google.
The above line be utilize the LC80440342014077LGN00 Landsat file from google ‘s archive.
You ‘ll witness metadata for this file such angstrom the type, id, isthmus name, extent, etc. print to the console table.
after operate the above line and visit the metadata for the file, copy and paste the below line and iron ‘Run ‘ ./* Load an image and store it in a variable called 'image' */ var image = ee.Image('LANDSAT/LC8_L1T/LC80440342014077LGN00'); /* Center the map on the image and set the zoom level to 9*/ Map.centerObject(image, 9); /* Display the image */ Map.addLayer(image);after melt the above handwriting, the map should now be zoom inch to the slide of central california with angstrom blue, Landsat image overlie on peak of the default map.
This be the effect functionality of google land engine : get datum, load information technology in, and display/visualize information technology onto the map .
a another example, copy and paste the code below into the code editor and bid ‘Run ‘ ./* Load the image from the archive */ var image = ee.Image('LANDSAT/LC8_L1T/LC80440342014077LGN00'); /* Define visualization parameters in an object literal */ var vizParams = {bands: ['B5', 'B4', 'B3'], min: 5000, max: 15000, gamma: 1.3}; /* Center the map on the image and display */ Map.centerObject(image, 9); Map.addLayer(image, vizParams, 'Landsat 8 false color');This script will visualize the same datum merely now alone use band list ‘B5 ‘, ‘B4 ‘, and ‘B3 ‘ with extra parameter such ampere min, soap, and gamma extent .
lend the below code section to the editor and wardrobe ‘Run ‘ again.Read more : Google Maps – Wikipedia
var counties = ee.FeatureCollection('ft:1S4EB6319wWW2sWQDPhDvmSBIVrD3iEmCLYB7nMM'); Map.addLayer(counties, {}, 'counties');now all of the county indiana the united states should be visualize on the function .
Next steps
while the above section bring some of the core aspect of google earth engine, the example provide embody about vitamin a bare a information technology get.
If you ‘re concerned in diving thick into google earth engine, you toilet read the earth locomotive documentation which explain and leave example for mechanism such arsenic trickle, screen, dance band mathematics, map, reduce, disguise, etc .
a complete list of all data that you give birth access to via google ‘s datum catalog toilet be detect here .
