ee.Image.arrayGet

Para cada banda, uma banda de saída com o mesmo nome é criada com o valor na posição especificada extraído do pixel multidimensional de entrada nessa banda.

Uso	Retorna
Image.arrayGet(position)	Imagem

Argumento	Tipo	Detalhes
isso: image	Imagem	Matriz de onde pegar um elemento.
position	Imagem	As coordenadas do elemento a serem recebidas. É preciso haver tantas bandas escalares quanto dimensões na imagem de entrada.

Exemplos

Editor de código (JavaScript)

// A function to print the array for a selected pixel in the following examples.
function sampArrImg(arrImg) {
  var point = ee.Geometry.Point([-121, 42]);
  return arrImg.sample(point, 500).first().get('array');
}

// Create a 1D array image.
var arrayImg1D = ee.Image([0, 1, 2, 3, 4, 5]).toArray();
print('1D array image (pixel)', sampArrImg(arrayImg1D));
// [0, 1, 2, 3, 4, 5]

// Get the array value at a given position. Here we target the 4th element.
var position1D = ee.Image([3]);
var selectedElement1D = arrayImg1D.arrayGet(position1D);
print('Element at position [3] (4th element)', sampArrImg(selectedElement1D));
// [3]

// Create a 2D 2x3 array image (reshape the 1D array image).
var arrayImg2D = arrayImg1D.arrayReshape(ee.Image([2, 3]).toArray(), 2);
print('2D 2x3 array image (pixel)', sampArrImg(arrayImg2D));
// [[0, 1, 2],
//  [3, 4, 5]]

// Get the array element value at axis-0, position 0 and axis-1, position 2.
var position2D = ee.Image([0, 2]);
var selectedElement2D = arrayImg2D.arrayGet(position2D);
print('Element at position [0, 2]', sampArrImg(selectedElement2D));
// 2

Configuração do Python

Consulte a página Ambiente Python para informações sobre a API Python e como usar geemap para desenvolvimento interativo.

import ee
import geemap.core as geemap

Colab (Python)

# A function to print the array for a selected pixel in the following examples.
def samp_arr_img(arr_img):
  point = ee.Geometry.Point([-121, 42])
  return arr_img.sample(point, 500).first().get('array')

# Create a 1D array image.
array_img_1d = ee.Image([0, 1, 2, 3, 4, 5]).toArray()
display('1D array image (pixel):', samp_arr_img(array_img_1d))
# [0, 1, 2, 3, 4, 5]

# Get the array value at a given position. Here we target the 4th element.
position_1d = ee.Image([3])
selected_element_1d = array_img_1d.arrayGet(position_1d)
display(
    'Element at position [3] (4th element):',
    samp_arr_img(selected_element_1d)
)
# [3]

# Create a 2D 2x3 array image (reshape the 1D array image).
array_img_2d = array_img_1d.arrayReshape(ee.Image([2, 3]).toArray(), 2)
display('2D 2x3 array image (pixel):', samp_arr_img(array_img_2d))
# [[0, 1, 2],
#  [3, 4, 5]]

# Get the array element value at axis-0, position 0 and axis-1, position 2.
position_2d = ee.Image([0, 2])
selected_element_2d = array_img_2d.arrayGet(position_2d)
display(
    'Element at position [0, 2]:',
    samp_arr_img(selected_element_2d)
)
# 2