예제: Thiele 보간 및 회귀

함수 > 데이터 분석 > 곡선 맞춤 > 예제: Thiele 보간 및 회귀

예제: Thiele 보간 및 회귀

Thielecoeff를 사용합니다. Thiele 계수가 추출되므로 Thiele 함수는 일종의 회귀 방법이라 생각할 수 있습니다.

1. 끓는 물의 포화 온도를 측정하여 °C 단위로 나타내는 데이터 집합을 입력합니다.

2. Thiele 방법을 사용하여 곡선이 데이터 집합을 지나도록 보간합니다.

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        <id label="Function" xml:space="preserve" label-is-contextual="true">Thiele</id>
        <sequence>
          <id label="Variable" xml:space="preserve" label-is-contextual="true">P</id>
          <id label="Variable" xml:space="preserve" label-is-contextual="true">coeff</id>
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3. 다항식 회귀 방법을 사용하여 곡선이 데이터 집합을 지나도록 맞춥니다.

4. 데이터 집합과 보간된 곡선 두 개를 도표화합니다.

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      <graph-size width="457.399999999999" height="230.4" />
      <axes>
        <xAxis rank="1" legend-position="PlotBoundaryBottom" start="0" end="220">
          <axisLine position="bottom" positionticmark="-1" legendWidth="92.1466666666667" />
          <axisGrid>
            <gridFrequency>12</gridFrequency>
            <gridLabels display="true" />
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            <tickMarks display="true" />
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        <yAxis rank="1" legend-position="PlotBoundaryLeft" start="290" end="675">
          <axisLine position="origin" positionticmark="0" legendWidth="97.29" />
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            <gridFrequency>12</gridFrequency>
            <gridLabels display="true" />
            <gridLines />
            <tickMarks display="true" />
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5. Thiele 방법을 사용하여 얻은 계산 결과를 증기표에 있는 두 개의 중점과 비교합니다.

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      <matrix rows="3" cols="2">
        <str xml:space="preserve"> mid-points </str>
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          <scale />
          <real>290.52</real>
          <id label="Unit" xml:space="preserve" label-is-contextual="true">°C</id>
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        <apply>
          <scale />
          <real>327.78</real>
          <id label="Unit" xml:space="preserve" label-is-contextual="true">°C</id>
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        <str xml:space="preserve">calculated</str>
        <apply>
          <id label="Variable" xml:space="preserve" label-is-contextual="true">TI</id>
          <apply>
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            <real>75</real>
            <id label="Unit" xml:space="preserve">bar</id>
          </apply>
        </apply>
        <apply>
          <id label="Variable" xml:space="preserve" label-is-contextual="true">TI</id>
          <apply>
            <scale />
            <real>125</real>
            <id label="Unit" xml:space="preserve">bar</id>
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      <unitOverride>
        <placeholder />
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계산된 데이터 점이 표에 나와 있는 데이터와 매우 가깝게 일치합니다.

6. Thiele로 보간된 곡선을 사용하여 해발 2250m의 멕시코시티에서 물이 끓는 온도를 계산합니다.

참조

IAPWS(International Association for the Properties of Water and Steam) 사이트(http://www.iapws.org)를 참조하십시오.