Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Creating a formula from plot points

  1. Oct 26, 2013 #1
    Hallo all...

    I have a couple of plot values that I am trying to derive a formula from. The points are almost linear but not quite...

    Was hoping someone could shed some light on how to go about this...
    I have Matlab 7.1, would like to use it if at all possible....

    Any help would be appreciated.
  2. jcsd
  3. Oct 26, 2013 #2

    Simon Bridge

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Welcome to PF;
    Turning a plot into an equation is called regression analysis.
    You have to start out with a good idea of what the underlying equation should be before you start.

    If you only have two points, then you can only plot a line - I'm guessing you mean you have a couple of datasets that, when you graph them, make something that looks like it's trying to be a line.

    The matlab function you want will be: polyfit
    ... you want to find the line y=mx+c that best fits the data.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook