Curve Fitting

Here’s a quick example. Say you have data that looks like this:

To create a curve fit, click on the curve fit tab, select the line you want to fit to (using the next and prev links) and then click on "Create a curve fit for this line"

After clicking on the link, you'll see a dialog like this:

The data is roughly quadratic, so you want to fit it with an equation like this: y = Ax² + B. The equation has two variables: A and B. There should already be one variable made for you, so click on ‘create new variable’ to make a second. Now name the first A, and set its starting value to 1.0. Name the second B and set its starting value to 1.0 as well.

Enter the equation in the equation box like this: A*x**2+B
For more information on equations, go to the curvefit equation help page.

Your curve fit form should look like this now:

You can leave everything else as is. To actually do the curve fit, click on the ‘save data and update graph button’. You should see the results of the curve fit in the preference form, something like this:

Your graph will look like this:

For help on making that note on the graph look nicer, check out the text formatting tutorial.