示例：使用极角

函数 > 制图 > 示例：使用极角

示例：使用极角

1. 定义两个长度相等的矢量来表示 x 和 y 坐标。

2. 使用 angle 和 atan2 函数来获得 x 和 y 坐标的对应角。

不在 (0,0) 处定义 atan2。

3. 使用 x 坐标计算半径矢量，并绘制结果。

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        <radialAxis rank="1" legend-position="PlotBoundaryRight" start="0" end="5">
          <axisLine position="origin" positionticmark="2" legendWidth="59.48" />
          <axisGrid>
            <gridFrequency>6</gridFrequency>
            <gridLabels display="true" />
            <gridLines />
            <tickMarks display="true" />
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          <axisLabel />
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            <startValue resultRef="44">
              <real xmlns="http://schemas.mathsoft.com/math50">0</real>
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            <endValue>
              <placeholder xmlns="http://schemas.mathsoft.com/math50" />
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          </radialDomain>
        </radialAxis>
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4. 使用 atan2 函数的结果计算半径，绘制其并将其与先前绘图进行比较。

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      <title class="- topic/title " wwtype:type="Paragraph" xmlns:wwtype="urn:WebWorks-Type-Schema" />
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          <traceStyle color="#FF00008B" symbol="x" line-weight="1" line-style="Solid">lines</traceStyle>
        </trace>
      </traces>
      <graph-size width="231.2" height="231.2" />
      <axes>
        <angularAxis rank="1" legend-position="PlotBoundaryBottom" start="0" end="360">
          <axisLine position="origin" positionticmark="6" legendWidth="35.3633333333333" />
          <axisGrid>
            <gridFrequency>13</gridFrequency>
            <gridLabels display="true" />
            <gridLines />
            <tickMarks display="true" />
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          <axisLabel />
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          <plotEquations>
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                <id xml:space="preserve" xmlns="http://schemas.mathsoft.com/math50">b</id>
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        </angularAxis>
        <radialAxis rank="1" legend-position="PlotBoundaryRight" start="0" end="5">
          <axisLine position="origin" positionticmark="2" legendWidth="67.46" />
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            <gridFrequency>6</gridFrequency>
            <gridLabels display="true" />
            <gridLines />
            <tickMarks display="true" />
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          <axisLabel />
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          <plotEquations>
            <plotEquation>
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                <id xml:space="preserve" xmlns="http://schemas.mathsoft.com/math50">r2</id>
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              <math resultRef="58">
                <placeholder xmlns="http://schemas.mathsoft.com/math50" />
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          <radialDomain scale-type="linear" auto-scale="true">
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这两个绘图相同。