Speed Learning

https://docs.google.com/presentation/d/1KZmOOvpz3kMSBdEHVWG8RLuGYBmTkqZyyWMuYbJZeMo/edit?usp=sharing 

//ENVB 530 (Adv. GIS for Natural Resource Mgmt), McGill University Winter 2022

//Speed Learning Presentation (GEE Script)

//Syntax: Javascript

//Eidan Willis

var landsat8_sr = ee.ImageCollection("LANDSAT/LC08/C01/T1_SR"); //Upload SR Imagery (note: collection is deprecated)

var srImage = ee.Image(landsat8_sr

    .filterBounds(ee.Geometry.Point(-120.31077, 37.55858))

    .filterDate('2013-09-15', '2013-09-27')

    .sort('CLOUD_COVER')

    .first());

Map.centerObject(ee.Geometry.Point(-120.31077, 37.55858), 11);

Map.addLayer(ee.Image(srImage.select('B5')), {}, 'Band 5 (NIR) Surface Reflectance');

var uiDisplayFlag = true

if (uiDisplayFlag) {

    // Create User Interface portion --------------------------------------------------

    // Create a panel to hold our widgets.

    var panel = ui.Panel();

    panel.style().set('width', '500px');

    // Create an intro panel with labels.

    var intro = ui.Panel([

        ui.Label({

            value: 'My User Interface',

            style: {

                fontSize: '20px',

                fontWeight: 'bold'

            }

        }),

        ui.Label('Click a point on the map to inspect.')

    ]);

    panel.add(intro);

    Map.style().set('cursor', 'crosshair');

    // Name panels to hold lon/lat values of clicked point on map

    var lon = ui.Label();

    var lat = ui.Label();

    // Display coords side-by-side

    panel.add(ui.Panel([lon, lat], ui.Panel.Layout.flow('horizontal'))); 

    //Register a callback to be executed when the map is clicked

    Map.onClick(function(coords) {

        // Update the lon/lat panel with values from the click event

        lon.setValue('longitude: ' + coords.lon.toFixed(5)),

        lat.setValue('latitude: ' + coords.lat.toFixed(5));

        var point = ee.Geometry.Point(coords.lon, coords.lat);

        var buffer = ee.FeatureCollection(point.buffer(1e4));

        var distribution = ee.FeatureCollection.randomPoints(buffer);

        var myHistogram = ui.Chart.image.histogram({

            image: srImage.select('B5'), //Using NIR band from a Surface Reflectance image

            region: distribution

            });

        myHistogram.setOptions({

            title: 'Histogram of Near Infrared Surface Reflectance (B5)',

            hAxis: {

              title: 'NIR Value', //Specify horizontal axis title

              //viewWindow: {min: 0, max: 750} <- Do this if you want to resize the x-axis

            },  

            vAxis: {

              title: 'Count'  //Specify vertical axis title

            },                  

            legend: {

              position: 'none'  //Hide the legend

            }                

        });

        panel.widgets().set(2, myHistogram);

    });

    Map.style().set('cursor', 'crosshair');

    // Add the panel to the ui.root.

    ui.root.insert(0, panel);

}