title: Excel interpolation with a few cells of same values in consecutive order
body: <p>the data I'm trying to interpolate looks like this:</p>
  
  <pre><code>=X= 
  0
  0
  0
  0
  0
  0.5
  1
  3.1
  5.5
  6.2
  8.5
  
  =Y=
  0.019607843
  0.019607843
  0.019607843
  0.019607843
  0.019607843
  0.117647059
  0.137254902
  0.156862745
  0.176470588
  0.196078431
  0.215686275
  
  =Z=
  0.019607843
  0.039215686
  0.058823529
  0.078431373
  0.098039216
  0.117647059
  0.137254902
  0.156862745
  0.176470588
  0.196078431
  0.215686275
  0.235294118
  </code></pre>
  
  <p>I'm using the <a href="http://www.xlxtrfun.com/XlXtrFun/XlXtrFun.htm" rel="nofollow">http://www.xlxtrfun.com/XlXtrFun/XlXtrFun.htm</a> addin. In a cell I have the interpolation formula from this addin, it works correctly most of the time except with this particular set of data.</p>
  
  <p>in <strong>AM1</strong> I have this code: </p>
  
  <blockquote>
    <p>=Interpolate($F$2:$F$51,$D$2:$D$51,M2,TRUE,FALSE)</p>
  </blockquote>
  
  <p>where column F is the Y Data D is the X data and M is Z</p>
  
  <p>the problem with it is that in the X set of data there is consecutive values of 0, so in the cell with the formula I get a <strong>#NUM!</strong></p>
  
  <p>I tried altering the 0's slightly to 0.1 0.2 etc. after that it works correctly so I know the formula is right, however with this data I can't alter it or it will drastically change results in the end. So does anyone know of a way I can keep these values and keep a correct interpolation?</p>