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ee.Array.firstNonZero
Mantieni tutto organizzato con le raccolte
Salva e classifica i contenuti in base alle tue preferenze.
Seleziona il primo valore se è diverso da zero e il secondo valore in caso contrario, in base a ciascun elemento.
| Utilizzo | Resi |
|---|
Array.firstNonZero(right) | Array |
| Argomento | Tipo | Dettagli |
|---|
questo: left | Array | Il valore a sinistra. |
right | Array | Il valore a destra. |
Esempi
Editor di codice (JavaScript)
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]]));
Configurazione di Python
Consulta la pagina
Ambiente Python per informazioni sull'API Python e sull'utilizzo di
geemap per lo sviluppo interattivo.
import ee
import geemap.core as geemap
Colab (Python)
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]]))
Salvo quando diversamente specificato, i contenuti di questa pagina sono concessi in base alla licenza Creative Commons Attribution 4.0, mentre gli esempi di codice sono concessi in base alla licenza Apache 2.0. Per ulteriori dettagli, consulta le norme del sito di Google Developers. Java è un marchio registrato di Oracle e/o delle sue consociate.
Ultimo aggiornamento 2025-07-29 UTC.
[null,null,["Ultimo aggiornamento 2025-07-29 UTC."],[[["\u003cp\u003e\u003ccode\u003eArray.firstNonZero()\u003c/code\u003e selects the first array's element if it's non-zero; otherwise, it selects the corresponding element from the second array.\u003c/p\u003e\n"],["\u003cp\u003eThis function operates element-wise on two input arrays (\u003ccode\u003eleft\u003c/code\u003e and \u003ccode\u003eright\u003c/code\u003e).\u003c/p\u003e\n"],["\u003cp\u003eIf the \u003ccode\u003eleft\u003c/code\u003e array element is 0, the corresponding element from the \u003ccode\u003eright\u003c/code\u003e array is chosen.\u003c/p\u003e\n"],["\u003cp\u003eThe function returns a new array containing the selected elements.\u003c/p\u003e\n"],["\u003cp\u003eIt's useful for scenarios like conditional data selection based on zero/non-zero values.\u003c/p\u003e\n"]]],["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"],null,["# ee.Array.firstNonZero\n\nOn an element-wise basis, selects the first value if it is non-zero, and the second value otherwise.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-----------------------------|---------|\n| Array.firstNonZero`(right)` | Array |\n\n| Argument | Type | Details |\n|--------------|-------|-----------------------|\n| this: `left` | Array | The left-hand value. |\n| `right` | Array | The right-hand value. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\nvar empty = ee.Array([], ee.PixelType.int8());\nprint(empty.firstNonZero(empty)); // []\n\nprint(ee.Array([0]).firstNonZero(0)); // [0]\nprint(ee.Array([0]).firstNonZero([0])); // [0]\nprint(ee.Array([0]).firstNonZero([1])); // [1]\nprint(ee.Array([2]).firstNonZero([3])); // [2]\nprint(ee.Array([1]).firstNonZero([0])); // [1]\n\nprint(ee.Array([-1, 0, 1]).firstNonZero([2, -1, 2])); // [-1,-1,1]\n\n// [[1,2],[3,4]]\nprint(ee.Array([[1, 2], [0, 0]]).firstNonZero([[0, 0], [3, 4]]));\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\nempty = ee.Array([], ee.PixelType.int8())\ndisplay(empty.firstNonZero(empty)) # []\n\ndisplay(ee.Array([0]).firstNonZero(0)) # [0]\ndisplay(ee.Array([0]).firstNonZero([0])) # [0]\ndisplay(ee.Array([0]).firstNonZero([1])) # [1]\ndisplay(ee.Array([2]).firstNonZero([3])) # [2]\ndisplay(ee.Array([1]).firstNonZero([0])) # [1]\n\ndisplay(ee.Array([-1, 0, 1]).firstNonZero([2, -1, 2])) # [-1, -1, 1]\n\n# [[1, 2], [3, 4]]\ndisplay(ee.Array([[1, 2], [0, 0]]).firstNonZero([[0, 0], [3, 4]]))\n```"]]
