Aligning data sets not created with waveforms

[Quasispice]

I'm creating a tracking test where the user follows a computer generated line on a touch screen. How can I align and resample these two sets of data (each set is an array of time, X, and Y coordinates)?

[Khalid]

Hello,

I am afraid I don't fully understand the setup or the issue here. What do you mean by "the user follows a computer generated line on a touch screen?" Do you mean that the user actually touches the screen and tries to follow a line on the screen with his finger? If this is the case, what are you trying to plot?

Please write back with more details.

Regards,

Khalid

[Quasispice]

Yes, that is exactly right. What I want to do is line up the coordinates of the line and the touch for each time so that I can calculate error. I'd then like to sample this data at a given rate so that the data file doesn't get too big.
Thanks for your help!

[Khalid]

I now understand what you're trying to do. You basically have to take the difference between the Y values for the two plots (the computer-generated one, and the touch-generated), for each value of X. X, in-fact will be the same for both the plots as you want to compare at a given time.

You can plot the resulting difference as the Y values against the same X values.

I have attached a screenshot showing this. Hope this gives you some ideas.

Khalid