How can i make an average plot of 2 unequal data sets?

Hi all,

I have data from 2 different experiments i conducted. As can be seen in the picture i have data set1 and data set2 and their corresponding plots. Now i wish to make a plot which is roughly an average of the two data sets but the data points i have are unequal so i do not know how to take a mean of the two or make confidence interval maybe. I would be grateful for any suggestions, thanks.

[dpb]

Interpolate the two with perhaps some smoothing to a common matching set of independent variable values and then average those results.

[aditya palawat]

Hi dpb, thanks for the reply. can you please guide me a bit with a simpler example or piece of code? i am only a beginner in matlab,thanks.

Answer 1

[Krishna Zanwar]

Hey Aditya,

This problem can be solved by 1D interpolation,

Let the X axis limits be 'Xmin', 'Xmax'.

And the data of X and Y axis be stored in 'X_data' , 'Y_data'.

For the second signal let them be stored in 'X_data_1' , 'Y_data_1';

You can sample the data at interval of 'X_int'.

Now

Xnew=Xmin:X_int:X_max;
Ynew=interp1(X_data,Y_data,Xnew);

You can follow the same procedure for 2nd data set.

Ynew_1=interp1(X_data_1, Y_data_1, Xnew);

Now you can get the average Yavg as-

Yavg=(Ynew+Ynew_1)/2;

And plot it against Xnew-

plot(Xnew,Yavg)

More information on 1D interpolation can be found here.

Hope this helps.

[aditya palawat]

Hi krishna, thanks for the asnwer. I was able to get the average!