Finding velocity given horizontal position, vertical position and time coordinates and definition of derivative.

For my latest physics lab, we shot two balls of different weights out of a "cannon" and used a video camera to record their x and y position over time. I have two sets of data, time vs x position and time vs y position. I need to manually find the derivative using this definition of the derivative: x'(t)=v(t)= (x(t+deltat)-x(t))/deltat (where x is the x position and t is time and deltat is the difference between time increments, .036667). I have about twenty points or so in a excel file. I am very new to matlab and was wondering if there was a way to write something in matlab to take my data, and use this equation to find the velocity at a given time. Any help is appreciated. Hopefully I explained myself well enough..

Answer 1

[James Tursa]

Some hints:

Import the data into MATLAB.

Look at the doc for the function called diff.