How to find and plot the absolut average error of a fittet curve to a Set of Data

In a for Loop I have my Data:

x_relevant{i} = x{i}(idx_min{i}:idx_max{i})

y_relevant{i} = y{i}(idx_min{i}:idx_max{i})

plot(x_relevant{i},y_relevant{i},'color',c2{i},'Marker','.','linestyle','none')

hold on

And a fittet linear Regression:

p{i} = polyfit(x_relevant{i}, y_relevant{i},1)

fit = polyval(p{i},x_relevant{i})

plot(x_relevant{i},fit,'color',c{i},'LineWidth',2)

hold on

How do I find the Standard error of this fitted curve?

Answer 1

[Ameer Hamza]

You can add the absolute error between actual datapoints and fitted curve like this

p{i} = polyfit(x_relevant{i}, y_relevant{i},1)
fit = polyval(p{i},x_relevant{i})
plot(x_relevant{i},fit,'color',c{i},'LineWidth',2)
hold on
plot(x_relevant{i},abs(fit-y_relevant{i}),'color',c{i},'LineWidth',2)