finding the error between two curves from a fig

35 views (last 30 days)
I have a fig, the onee in attaced (example).
Considering the green one the true value, how can I evaluete the error of the second?
P.S.
I have Matlab 2014b
  1 Comment
Paul Rogers
Paul Rogers on 19 Jul 2020
someone suggested this and theen deleted, but it's not working:
Open the figure and run the following commands to calculate the MSE .
% get current axes
ax = gca;
% get Y data of green and blue lines
GreenLineY = ax.Children(1).YData ;
BlueLineY = ax.Children(2).YData;
% MSE
MeanSquaredError = (GreenLineY - BlueLineY) .^2;

Sign in to comment.

Accepted Answer

Takumi
Takumi on 19 Jul 2020
I used the findall function to find out what was plotted.
I noticed that some of the lines containing the NaN values were plotted as nonsense.
The lines you're trying to compare are probably h(2) and h(6).
In addition, the blue line contains NaN values that need to be removed.
Finally, we need to align the number of elements to compute the error, so we interpolate.
% get current axes
ax = gca;
% find object
h = findall(ax);
% get Y data of green and blue lines
GreenLineX = h(2).XData;
GreenLineY = h(2).YData;
BlueLineX = h(6).XData;
BlueLineY = h(6).YData;
% eliminate NaN
BlueLineX = rmmissing(BlueLineX);
BlueLineY = rmmissing(BlueLineY);
% interpolation
GreenLineY_interp = interp1(GreenLineX,GreenLineY,BlueLineX,'spline');
% MSE
MeanSquaredError = mean((GreenLineY_interp - BlueLineY).^2);
figure
plot(GreenLineX,GreenLineY,'-g');
hold on
plot(BlueLineX,BlueLineY,'-b');
  6 Comments
Takumi
Takumi on 19 Jul 2020
I have installed MATLAB version 2014b and it worked fine.
Paul Rogers
Paul Rogers on 19 Jul 2020
sorry, It works. I just did a very stuoid mistake!
You're great, thanks for helping me.

Sign in to comment.

More Answers (0)

Categories

Find more on Graphics Performance in Help Center and File Exchange

Products


Release

R2014b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!