Problem 561. Find the jerk

No, it's not the author of this problem...

Jerk is the rate of change in acceleration over time of an object. So, if given the position of an object over time in the form of a 1-by-N vector, return the indices i where there is nonzero jerk.

Super rad bonus hint: The signal you need to find the jerk of will be given by the variable sig, created with the commands

h = 0.065; % stepsize
t = -10:h:10;
sigCoefs = 2*rand(1,3)-1;
sig = polyval(sigCoefs,t);
breakPoint = randi(length(sig)-2)+1;
sig(breakPoint) = (1.01)*sig(breakPoint); % this creates a nonzero jerk

Check the signal visually with

plot(t,sig,'k.-')

Now, using just sig, determine breakPoint.