AI-generated Key Takeaways
-
The
arrayDotProduct
function computes the dot product of corresponding 1-D array bands from two input images. -
This function is called on the first image (
image1
) and takes the second image (image2
) as an argument. -
Both input images,
image1
andimage2
, must be images containing 1-D array vectors. -
The function returns an
Image
where each pixel's value is the dot product of the corresponding pixel's 1-D arrays from the input images.
Usage | Returns |
---|---|
Image.arrayDotProduct(image2) | Image |
Argument | Type | Details |
---|---|---|
this: image1 | Image | First array image of 1-D vectors. |
image2 | Image | Second array image of 1-D vectors. |
Examples
Code Editor (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
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