ee.Image.arrayDotProduct

：計算輸入圖片各波段中每對 1 維陣列的點積。

用量傳回
Image.arrayDotProduct(image2)圖片
引數類型詳細資料
這個：image1圖片一維向量的第一個陣列圖片。
image2圖片一維向量的第二個陣列圖片。

範例

程式碼編輯器 (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 1D array image.
var arrayImg1Da = ee.Image([0, 1, 2]).toArray();
print('1D array image A (pixel)', sampArrImg(arrayImg1Da));
// [0, 1, 2]

// A second 1D array image of the same length.
var arrayImg1Db = ee.Image([3, 4, 5]).toArray();
print('1D array image B (pixel)', sampArrImg(arrayImg1Db));
// [3, 4, 5]

// Calculate the dot product for the two 1D arrays.
var test = arrayImg1Da.arrayDotProduct(arrayImg1Db);
print('A⋅B = 0(3) + 1(4) + 2(5) = ', sampArrImg(test));
// 14

Python 設定

請參閱 Python 環境頁面，瞭解 Python API 和如何使用 geemap 進行互動式開發。

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 1D array image.
array_img_1d_a = ee.Image([0, 1, 2]).toArray()
print('1D array image A (pixel):', samp_arr_img(array_img_1d_a).getInfo())
# [0, 1, 2]

# A second 1D array image of the same length.
array_img_1d_b = ee.Image([3, 4, 5]).toArray()
print('1D array image B (pixel):', samp_arr_img(array_img_1d_b).getInfo())
# [3, 4, 5]

# Calculate the dot product for the two 1D arrays.
test = array_img_1d_a.arrayDotProduct(array_img_1d_b)
print('A⋅B = 0(3) + 1(4) + 2(5) = ', samp_arr_img(test).getInfo())
# 14