ee.Array.firstNonZero
On an element-wise basis, selects the first value if it is non-zero, and the second value otherwise.
| Usage | Returns |
|---|
Array.firstNonZero(right) | Array |
| Argument | Type | Details |
|---|
this: left | Array | The left-hand value. |
right | Array | The right-hand value. |
Examples
var empty = ee.Array([], ee.PixelType.int8());
print(empty.firstNonZero(empty)); // []
print(ee.Array([0]).firstNonZero(0)); // [0]
print(ee.Array([0]).firstNonZero([0])); // [0]
print(ee.Array([0]).firstNonZero([1])); // [1]
print(ee.Array([2]).firstNonZero([3])); // [2]
print(ee.Array([1]).firstNonZero([0])); // [1]
print(ee.Array([-1, 0, 1]).firstNonZero([2, -1, 2])); // [-1,-1,1]
// [[1,2],[3,4]]
print(ee.Array([[1, 2], [0, 0]]).firstNonZero([[0, 0], [3, 4]]));
Python setup
See the
Python Environment page for information on the Python API and using
geemap for interactive development.
import ee
import geemap.core as geemap
empty = ee.Array([], ee.PixelType.int8())
display(empty.firstNonZero(empty)) # []
display(ee.Array([0]).firstNonZero(0)) # [0]
display(ee.Array([0]).firstNonZero([0])) # [0]
display(ee.Array([0]).firstNonZero([1])) # [1]
display(ee.Array([2]).firstNonZero([3])) # [2]
display(ee.Array([1]).firstNonZero([0])) # [1]
display(ee.Array([-1, 0, 1]).firstNonZero([2, -1, 2])) # [-1, -1, 1]
# [[1, 2], [3, 4]]
display(ee.Array([[1, 2], [0, 0]]).firstNonZero([[0, 0], [3, 4]]))
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["`Array.firstNonZero()` selects the first array's element if it's non-zero; otherwise, it selects the corresponding element from the second array."],["This function operates element-wise on two input arrays (`left` and `right`)."],["If the `left` array element is 0, the corresponding element from the `right` array is chosen."],["The function returns a new array containing the selected elements."],["It's useful for scenarios like conditional data selection based on zero/non-zero values."]]],["The `firstNonZero` method compares two arrays (`left` and `right`) element-wise. If an element in the `left` array is non-zero, that value is selected. Otherwise, the corresponding element from the `right` array is chosen. The method returns a new array where each element is the result of this comparison. Both JavaScript and Python examples show how to implement and the result. The return value is an array.\n"]]