ee.Image.arrayArgmax

Calcule les indices de position de la valeur maximale dans l'image des valeurs du tableau. S'il existe plusieurs occurrences du maximum, les index reflètent la première.

UtilisationRenvoie
Image.arrayArgmax()Image
ArgumentTypeDétails
ceci : imageImageImage d'entrée.

Exemples

Éditeur de code (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, 5, 2, 3, 4]).toArray();
print('1D array image (pixel)', sampArrImg(arrayImg1D));
// [0, 1, 5, 2, 3, 4]

// Get the position of the maximum value in a 1D array.
var maxValue1D = arrayImg1D.arrayArgmax();
print('Position of the maximum 1D array value', sampArrImg(maxValue1D));
// [2]

// 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, 5],
//  [2, 3, 4]]

// Get the position of the maximum value in a 2D array.
var maxValue2D = arrayImg2D.arrayArgmax();
print('Position of the maximum 2D array value', sampArrImg(maxValue2D));
// [0, 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 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, 5, 2, 3, 4]).toArray()
print('1D array image (pixel):', samp_arr_img(array_img_1d).getInfo())
# [0, 1, 5, 2, 3, 4]

# Get the position of the maximum value in a 1D array.
max_value_1d = array_img_1d.arrayArgmax()
print(
    'Position of the maximum 1D array value:',
    samp_arr_img(max_value_1d).getInfo()
    )
# [2]

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

# Get the position of the maximum value in a 2D array.
max_value_2d = array_img_2d.arrayArgmax()
print(
    'Position of the maximum 2D array value:',
    samp_arr_img(max_value_2d).getInfo()
)
# [0, 2]