finding the error between two curves from a fig

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

[Paul Rogers]

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;

Answer 1

[Takumi]

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');

[Paul Rogers]

thatnks, man

but I got stuck here when I run the program:

GreenLineX = h(2).XData; 

I don't know if it helps, but I have Matlab2014b

[Takumi]

% 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= BlueLineX(~isnan(BlueLineX));
 BlueLineY= BlueLineY(~isnan(BlueLineY));
% 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');

[Paul Rogers]

I get this error message:

Index exceeds matrix dimensions.

Error in Mikko_4 (line 74)
BlueLineX = h(6).XData;
 

[Takumi]

Really? Your version is 2014b right?

[Takumi]

I have installed MATLAB version 2014b and it worked fine.

[Paul Rogers]

sorry, It works. I just did a very stuoid mistake!

You're great, thanks for helping me.