ee.Image.toArray

Concatène les pixels de chaque bande en un seul tableau par pixel. Le résultat sera masqué si des bandes d'entrée sont masquées.

UtilisationRenvoie
Image.toArray(axis)Image
ArgumentTypeDétails
ceci : imageImageImage des bandes à convertir en tableau par pixel. Les bandes doivent comporter des pixels scalaires ou des pixels de tableau avec une dimensionnalité égale.
axisEntier, valeur par défaut : 0Axe le long duquel concaténer. Il doit être compris entre 0 et la dimension des entrées. Si l'axe est égal à la dimension des entrées, le résultat aura une dimension de plus que les entrées.

Exemples

Éditeur de code (JavaScript)

// A function to print arrays 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');
}

// A 3-band image of constants.
var img = ee.Image([0, 1, 2]);
print('3-band image', img);

// Convert the 3-band image to an array image. The resulting array image has a
// single band named "array". The "array" band stores the per-pixel band values
// from the input ee.Image as a 1D array.
var arrayImg1D = img.toArray();
print('1D array image', arrayImg1D);

// Sample a single pixel to see its 1D array using the `sampArrImg` function
// defined above. Similar arrays are present for all pixels in a given array
// image; looking at just one helps conceptualize the structure.
print('1D array image (pixel)', sampArrImg(arrayImg1D));
// [0, 1, 2]

// Array images can be displayed to the Code Editor map and queried with the
// inspector tool. Per-pixel, the first element in the array is shown.
// Single-band grayscale is used to represent the data. Style parameters `min`
// and `max` are valid. Styling the layer with the Code Editor's layer
// visualization tool is invalid.
Map.addLayer(arrayImg1D, {min: 0, max: 2}, 'Image array');

// Create a 2D array image by concatenating the values in a 1D array image
// along the 1-axis using `toArray(1)`. For a 3D array, apply `toArray(2)` to
// the result.
var arrayImg2D = arrayImg1D.toArray(1);
print('2D array image (pixel)', sampArrImg(arrayImg2D));
// [[0],
//  [1],
//  [2]]

Configuration de Python

Consultez la page Environnement Python pour en savoir plus sur l'API Python et sur l'utilisation de geemap pour le développement interactif.

import ee
import geemap.core as geemap

Colab (Python)

# A function to print arrays 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')


# A 3-band image of constants.
img = ee.Image([0, 1, 2])
display('3-band image', img)

# Convert the 3-band image to an array image. The resulting array image has a
# single band named "array". The "array" band stores the per-pixel band values
# from the input ee.Image as a 1D array.
array_img_1_d = img.toArray()
display('1D array image', array_img_1_d)

# Sample a single pixel to see its 1D array using the `samp_arr_img` function
# defined above. Similar arrays are present for all pixels in a given array
# image looking at just one helps conceptualize the structure.
display('1D array image (pixel)', samp_arr_img(array_img_1_d))
# [0, 1, 2]

# Array images can be displayed to the Code Editor map and queried with the
# inspector tool. Per-pixel, the first element in the array is shown.
# Single-band grayscale is used to represent the data. Style parameters `min`
# and `max` are valid. Styling the layer with the Code Editor's layer
# visualization tool is invalid.
m = geemap.Map()
m.add_layer(array_img_1_d, {'min': 0, 'max': 2}, 'Image array')
display(m)

# Create a 2D array image by concatenating the values in a 1D array image
# along the 1-axis using `toArray(1)`. For a 3D array, apply `toArray(2)` to
# the result.
array_img_2_d = array_img_1_d.toArray(1)
display('2D array image (pixel)', samp_arr_img(array_img_2_d))
# [[0],
#  [1],
#  [2]]