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Calculating uncertainty of a function in Mathematica

  1. May 3, 2009 #1
    I have a function of which I'm trying to determine the uncertainty. I'm using Mathematica and I can't get it to work. However, I don't see what I'm doing wrong. My uncertainty has the same value as the function itself, only a factor 10^7 higher. That is of course completely wrong, but I don't see where I'm going wrong. Could anyone please take a look?

    http://home.orange.nl/~kuip3148/Differentieermethode.nb [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 22, 2009 #2


    Staff: Mentor

    Hi Shukie,

    This is probably a little late, but your formula for the propagation of errors is wrong. Each term should be of the form SDx²(df/dx)² where SDx is the standard deviation of x. You calculate the (df/dx)² part of each term but never use the SDx² part. Also, you forgot to square the one for R.
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