ee.Array.cos

按元素计算以弧度表示的输入的余弦。

用法	返回
Array.cos()	数组

参数	类型	详细信息
此：input	数组	输入数组。

示例

代码编辑器 (JavaScript)

var π = Math.PI;
print(ee.Array([-π]).cos());  // [-1]
print(ee.Array([-π / 2.0]).cos());  // [Almost zero]
print(ee.Array([0]).cos());  // [1]
print(ee.Array([π / 2.0]).cos());  // [Almost zero]
print(ee.Array([π]).cos());  // [-1]

var start = -π;
var end = π;
var points = ee.Array(ee.List.sequence(start, end, null, 50));
var values = points.cos();

// Plot cos() 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: '-π'},
          {v: 0, f: 0},
          {v: end, f: 'π'}]
      },
      vAxis: {
        title: 'cos(x)',
        ticks: [
          {v: -1, f: -1},
          {v: 0, f: 0},
          {v: 1, f: 1}]
      },
      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

π = math.pi
display(ee.Array([-π]).cos())  # [-1]
display(ee.Array([-π / 2.0]).cos())  # [Almost zero]
display(ee.Array([0]).cos())  # [1]
display(ee.Array([π / 2.0]).cos())  # [Almost zero]
display(ee.Array([π]).cos())  # [-1]

start = -π
end = π
points = ee.Array(ee.List.sequence(start, end, None, 50))
values = points.cos()

df = pd.DataFrame({'x': points.getInfo(), 'cos(x)': values.getInfo()})

# Plot cos() defined above.
alt.Chart(df).mark_line().encode(
    x=alt.X('x', axis=alt.Axis(values=[start, 0, end])),
    y=alt.Y('cos(x)', axis=alt.Axis(values=[-1, 0, 1]))
)