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      <title>Setting Up Goal Seek</title>
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      <div class="title_topic4" id="xps10_pagetitle">Setting Up Goal Seek</div>
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      <p class="para_topic"> On choosing Options&rarr;Setup Goal Seek, the basic setup dialog displays. When Goal Seek is active, the following process is followed.</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item"> Make a guess for the variable value.</p>
         </li>
         <li>
            <p class="para_item"> Do a spreadsheet recalc.</p>
         </li>
         <li>
            <p class="para_item"> Update expression from the Active Range into the part (just like pressing Tools&rarr;Update NX Part).</p>
         </li>
         <li>
            <p class="para_item"> Do another spreadsheet recalc.</p>
         </li>
         <li>
            <p class="para_item"> Read the target cell and compare to the target value.</p>
         </li>
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      <p class="para_topic"> This process which is repeated until the target cell matches some target value within a tolerance. A specific mathematical calculation is performed, based on the type of goal seek in order to determine the next &quot;guess&quot;. For each method, an option button is available on the dialog to toggle OFF step 3 (Tools&rarr;Goal Seek&rarr;Perform NX Update), updating the NX expressions in the process above. Toggle OFF the expression update allows the goal seek to work just like the built-in spreadsheet goal seek function, and can improve performance if NX parameters are not being changed.</p>
      <p class="para_topic"> Not all functions will converge to a solution. Discontinuous functions in particular may not lend themselves to a solution. In some cases a &quot;guess&quot; at a solution may cause a floating-point error such as division by zero, and abort the solver. In many cases, the proper selection of either an initial guess or a selection of good upper and lower brackets can assist the process of convergence to a solution.</p>
      <p class="para_topic"> Regardless of the goal seek method, there are certain standard error conditions that can occur during the goal seek:</p>
      <ul>
         <li>
            <p class="para_item"> Input cell values are bad (i.e., 12 instead of A2 or A99999999999).</p>
         </li>
         <li>
            <p class="para_item"> Numeric input values are bad (i.e., a.4 instead of 1.4).</p>
         </li>
         <li>
            <p class="para_item"> The variable cell is empty. This implies the cell is not currently being used in a formula.</p>
         </li>
         <li>
            <p class="para_item"> The variable cell is not numeric.</p>
         </li>
         <li>
            <p class="para_item"> The target cell is empty; therefore no formula will be updated in the cell and goal seek has no value to compare to a target.</p>
         </li>
         <li>
            <p class="para_item"> The target cell is not a formula.</p>
         </li>
         <li>
            <p class="para_item"> A floating point error occurred in the target cell (such as division by zero)</p>
         </li>
         <li>
            <p class="para_item"> The iteration limit was reached without a convergence.</p>
         </li>
         <li>
            <p class="para_item"> The NX part update failed.</p>
         </li>
      </ul>
      <p class="para_topic"> Error conditions are reported by a message in the Spreadsheet message area along the bottom of the spreadsheet window.</p>
      <p class="para_topic"> The actual goal seek function is started through the Tools&rarr;Goal Seek menu option on the spreadsheet main menu bar.</p>
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