ee.Array.log
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Calcule le logarithme naturel de l'entrée, élément par élément.
Utilisation | Renvoie |
---|
Array.log() | Tableau |
Argument | Type | Détails |
---|
ceci : input | Tableau | Tableau d'entrée. |
Exemples
Éditeur de code (JavaScript)
print(ee.Array([Math.pow(Math.E, -1), 1, Math.E]).log()); // [-1,0,1]
var start = 0.1;
var end = 6;
var points = ee.Array(ee.List.sequence(start, end, null, 50));
var values = points.log();
// Plot log() defined above.
var chart = ui.Chart.array.values(values, 0, points)
.setOptions({
viewWindow: {min: start, max: end},
hAxis: {
title: 'x',
viewWindowMode: 'maximized',
ticks: [
{v: 0},
{v: 3},
{v: end}]
},
vAxis: {
title: 'log(x)',
ticks: [
{v: -3},
{v: 0},
{v: 3}]
},
lineWidth: 1,
pointSize: 0,
});
print(chart);
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)
import math
import altair as alt
import pandas as pd
display(ee.Array([pow(math.e, -1), 1, math.e]).log()) # [-1,0,1]
start = 0.1
end = 6
points = ee.Array(ee.List.sequence(start, end, None, 50))
values = points.log()
df = pd.DataFrame({'x': points.getInfo(), 'log(x)': values.getInfo()})
# Plot log() defined above.
alt.Chart(df).mark_line().encode(
x=alt.X('x', axis=alt.Axis(values=[0, 3, end])),
y=alt.Y('log(x)', axis=alt.Axis(values=[-3, 0, 3]))
)
Sauf indication contraire, le contenu de cette page est régi par une licence Creative Commons Attribution 4.0, et les échantillons de code sont régis par une licence Apache 2.0. Pour en savoir plus, consultez les Règles du site Google Developers. Java est une marque déposée d'Oracle et/ou de ses sociétés affiliées.
Dernière mise à jour le 2025/07/26 (UTC).
[null,null,["Dernière mise à jour le 2025/07/26 (UTC)."],[[["\u003cp\u003eComputes the natural logarithm of each element in an input array.\u003c/p\u003e\n"],["\u003cp\u003eReturns an array with the same dimensions as the input array, containing the calculated logarithms.\u003c/p\u003e\n"],["\u003cp\u003eUsage involves calling the \u003ccode\u003e.log()\u003c/code\u003e method on an Earth Engine \u003ccode\u003eArray\u003c/code\u003e object.\u003c/p\u003e\n"]]],["The `Array.log()` function computes the natural logarithm of each element within an input array. It accepts an array as input and returns a new array containing the natural logarithm of each corresponding element. Example usage demonstrates calculating the logarithm of `[e^-1, 1, e]` resulting in `[-1, 0, 1]`. The function's application is further visualized via charts that display the calculated logarithmic values against a range of input values.\n"],null,["# ee.Array.log\n\nOn an element-wise basis, computes the natural logarithm of the input.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------|---------|\n| Array.log`()` | Array |\n\n| Argument | Type | Details |\n|---------------|-------|------------------|\n| this: `input` | Array | The input array. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\nprint(ee.Array([Math.pow(Math.E, -1), 1, Math.E]).log()); // [-1,0,1]\n\nvar start = 0.1;\nvar end = 6;\nvar points = ee.Array(ee.List.sequence(start, end, null, 50));\nvar values = points.log();\n\n// Plot log() defined above.\nvar chart = ui.Chart.array.values(values, 0, points)\n .setOptions({\n viewWindow: {min: start, max: end},\n hAxis: {\n title: 'x',\n viewWindowMode: 'maximized',\n ticks: [\n {v: 0},\n {v: 3},\n {v: end}]\n },\n vAxis: {\n title: 'log(x)',\n ticks: [\n {v: -3},\n {v: 0},\n {v: 3}]\n },\n lineWidth: 1,\n pointSize: 0,\n });\nprint(chart);\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\nimport math\nimport altair as alt\nimport pandas as pd\n\ndisplay(ee.Array([pow(math.e, -1), 1, math.e]).log()) # [-1,0,1]\n\nstart = 0.1\nend = 6\npoints = ee.Array(ee.List.sequence(start, end, None, 50))\nvalues = points.log()\n\ndf = pd.DataFrame({'x': points.getInfo(), 'log(x)': values.getInfo()})\n\n# Plot log() defined above.\nalt.Chart(df).mark_line().encode(\n x=alt.X('x', axis=alt.Axis(values=[0, 3, end])),\n y=alt.Y('log(x)', axis=alt.Axis(values=[-3, 0, 3]))\n)\n```"]]