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      <title>Regula-Falsi Goal Seek</title>
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      <div class="title_topic5" id="xps10_pagetitle">Regula-Falsi Goal Seek</div>
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      <p class="para_topic"> Regula-Falsi goal seek is also called False Position or Bracket goal seek. It works by finding two limits for the variable value that result in outputs that are above and below the target value (bracketing). The program then tightens the upper and lower limits until the solution is found within a tolerance. This method is basically the same as the spreadsheet Goal Seek function.</p>
      <p class="para_topic"> With Options&rarr;Setup Goal Seek set to the Regula Falsi Method, choosing Tools&rarr;Goal Seek, displays the Regula Falsi Goal Seek dialog. In the NX version of Regula Falsi Goal Seek you need to provide the following information:</p>
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               <p class="para_td"> Variable Cell</p>
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               <p class="para_td"> The cell location to change.</p>
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               <p class="para_td"> Target Cell</p>
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               <p class="para_td"> The cell location for the result.</p>
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               <p class="para_td"> Target Value</p>
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               <p class="para_td"> The desired result.</p>
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               <p class="para_td"> Lower Bracket</p>
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               <p class="para_td"> The optional lower bracket value.</p>
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               <p class="para_td"> Upper Bracket</p>
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               <p class="para_td"> The optional upper bracket value.</p>
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               <p class="para_td"> Tolerance</p>
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               <p class="para_td"> The desired accuracy of convergence.</p>
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               <p class="para_td"> Max Iterations</p>
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               <p class="para_td"> The number of iterations allowed.</p>
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      </table><br><p class="para_topic"> The Variable Cell must be a cell with contents of some kind.</p>
      <p class="para_topic"> The Target Cell must be a cell with a formula.</p>
      <p class="para_topic"> The Upper and Lower bracket values are optional. If they are left blank, the program will use the current value of the variable cell as the lower bracket, and the upper bracket will be the variable cell value plus a small offset (0.12). Providing a good initial guess for the upper and lower bracket limits can decrease the time and number of iterations necessary to converge on a solution.</p>
      <p class="para_topic"> The Regula-Falsi Goalseek program first checks the bracket values to see if the target value is bracketed. If it is not, the program attempts to adjust the bracket values such that the target value is bracketed. Once the target is bracketed, the program begins to tighten the brackets until the target cell converges to the desired target value.</p>
      <p class="para_topic"> In addition to the normal error conditions for goal seek, possible Regula-Falsi error conditions include:</p>
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            <p class="para_item"> Bracket values could not be found.</p>
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      <p class="para_topic"> As described earlier, the Perform NX Update button selects whether the goal seek will actually cause the expressions defined in the active range to be sent to the NX part.  </p>
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