title: add a float value to a tuple
body: <p>I get x y coordinates from a vision tool as text(string). I need to add a constant value
   to every x - element in this string.</p>
  
  <p>with this statements a get a tuple of the original values and the command of my vision-
   tool needs a tuple as argument</p>
  
  <pre><code>above=GetValue('ObererBogen.FittedPoints')
  above=above.replace('(((','((')
  above=above.replace('),),)','))')
  above=eval(above)
  </code></pre>
  
  <p>now I have a tuple named above with x,y-coordinates.
   But how add a constant value to each x-value ?</p>