Plot - show fitting error

Hi,

Starting with a set of data points, I use a fitfun function to fit it to a nonlinear scaling function A^x.

Now, I would like to quantify the error of the fits themselves, to understand how the points deviate from the scaling function.

May I ask for any help to do this?

Thanks!

Answer 1

[darova]

A = 1.9;
x = linspace(0,4,50);
y = A.^x + rand(1,50);
res = fit(x',y','A.^x');
y1 = res.A.^x;

plot(x,y,'.',x,y1)
legend('data','fit')

figure
title('Error')
plot(x,y1-y)