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ee.Array.acos
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On an element-wise basis, computes the arccosine in radians of the input.
| Usage | Returns | Array.acos() | Array |
| Argument | Type | Details | this: input | Array | The input array. |
Examples
Code Editor (JavaScript)
print(ee.Array([-1]).acos()); // [π]
print(ee.Array([0]).acos()); // [π/2]
print(ee.Array([1]).acos()); // [0]
var start = -1;
var end = 1;
var points = ee.Array(ee.List.sequence(start, end, null, 50));
var values = points.acos();
// Plot acos() defined above.
var chart = ui.Chart.array.values(values, 0, points)
.setOptions({
viewWindow: {min: start, max: end},
hAxis: {
title: 'x',
viewWindowMode: 'maximized',
ticks: [
{v: start, f: start},
{v: 0, f: 0},
{v: end, f: end}]
},
vAxis: {
title: 'acos(x)',
ticks: [
{v: 0, f: 0},
{v: Math.PI / 2, f: 'π/2'},
{v: Math.PI, f: 'π'}]
},
lineWidth: 1,
pointSize: 0,
});
print(chart);
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
Colab (Python)
import math
import altair as alt
import pandas as pd
display(ee.Array([-1]).acos()) # [π]
display(ee.Array([0]).acos()) # [π/2]
display(ee.Array([1]).acos()) # [0]
start = -1
end = 1
points = ee.Array(ee.List.sequence(start, end, None, 50))
values = points.acos()
df = pd.DataFrame({'x': points.getInfo(), 'acos(x)': values.getInfo()})
# Plot acos() defined above.
alt.Chart(df).mark_line().encode(
x=alt.X('x', axis=alt.Axis(values=[start, 0, end])),
y=alt.Y('acos(x)', axis=alt.Axis(values=[0, math.pi / 2, math.pi]))
)
Except as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. For details, see the Google Developers Site Policies. Java is a registered trademark of Oracle and/or its affiliates.
Last updated 2024-09-19 UTC.
[null,null,["Last updated 2024-09-19 UTC."],[[["\u003cp\u003eCalculates the arccosine (inverse cosine) of each element in an input array.\u003c/p\u003e\n"],["\u003cp\u003eReturns a new array containing the arccosine values in radians.\u003c/p\u003e\n"],["\u003cp\u003eAccepts an array as input and operates on each element independently.\u003c/p\u003e\n"],["\u003cp\u003eProvides examples in JavaScript, Python, and Colab to demonstrate usage and visualization.\u003c/p\u003e\n"]]],["The `Array.acos()` function computes the arccosine (in radians) of each element within an input array. It accepts an array as input and returns a new array containing the arccosine values. Examples demonstrate its use with -1, 0, and 1, resulting in outputs of π, π/2, and 0 respectively. The examples also showcase plotting the function, with `x` values between -1 and 1 and corresponding `acos(x)` outputs.\n"],null,["# ee.Array.acos\n\nOn an element-wise basis, computes the arccosine in radians of the input.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|----------------|---------|\n| Array.acos`()` | 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([-1]).acos()); // [π]\nprint(ee.Array([0]).acos()); // [π/2]\nprint(ee.Array([1]).acos()); // [0]\n\nvar start = -1;\nvar end = 1;\nvar points = ee.Array(ee.List.sequence(start, end, null, 50));\nvar values = points.acos();\n\n// Plot acos() 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: start, f: start},\n {v: 0, f: 0},\n {v: end, f: end}]\n },\n vAxis: {\n title: 'acos(x)',\n ticks: [\n {v: 0, f: 0},\n {v: Math.PI / 2, f: 'π/2'},\n {v: Math.PI, f: 'π'}]\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([-1]).acos()) # [π]\ndisplay(ee.Array([0]).acos()) # [π/2]\ndisplay(ee.Array([1]).acos()) # [0]\n\nstart = -1\nend = 1\npoints = ee.Array(ee.List.sequence(start, end, None, 50))\nvalues = points.acos()\n\ndf = pd.DataFrame({'x': points.getInfo(), 'acos(x)': values.getInfo()})\n\n# Plot acos() defined above.\nalt.Chart(df).mark_line().encode(\n x=alt.X('x', axis=alt.Axis(values=[start, 0, end])),\n y=alt.Y('acos(x)', axis=alt.Axis(values=[0, math.pi / 2, math.pi]))\n)\n```"]]