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ee.Array.log
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
以元素为单位计算输入的自然对数。
示例
代码编辑器 (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);
Python 设置
如需了解 Python API 和如何使用 geemap
进行交互式开发,请参阅
Python 环境页面。
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]))
)
如未另行说明,那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可,并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情,请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC):2025-07-26。
[null,null,["最后更新时间 (UTC):2025-07-26。"],[[["\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```"]]