04_band_math.py

import ee
from ee_plugin import Map

# This function gets NDVI from Landsat 5 imagery.


def getNDVI(image):
    return image.normalizedDifference(['B4', 'B3'])


# Load two Landsat 5 images, 20 years apart.
image1 = ee.Image('LANDSAT/LT05/C01/T1_TOA/LT05_044034_19900604')
image2 = ee.Image('LANDSAT/LT05/C01/T1_TOA/LT05_044034_20100611')

# Compute NDVI from the scenes.
ndvi1 = getNDVI(image1)
ndvi2 = getNDVI(image2)

# Compute the difference in NDVI.
ndviDifference = ndvi2.subtract(ndvi1)

ndviParams = {'palette': ['#d73027', '#f46d43', '#fdae61',
                          '#fee08b', '#d9ef8b', '#a6d96a', '#66bd63', '#1a9850']}
ndwiParams = {'min': -0.5, 'max': 0.5, 'palette': ['FF0000', 'FFFFFF', '0000FF']}


Map.centerObject(image1, 10)
Map.addLayer(ndvi1, ndviParams, 'NDVI 1')
Map.addLayer(ndvi2, ndviParams, 'NDVI 2')
Map.addLayer(ndviDifference, ndwiParams, 'NDVI difference')