velocity and acceleration - apply filter

i use this code to obtain the velocity and acceleration from x,t data (by using central differences).

but as you can see now i need to apply some _filter _ (i think i should apply it in the x data also) . can anyone help me please?

[Ryan G]

It looks like you already acquired your data. How did you obtain the position data? Does your mechanism have accelerometers? What you're seeing and will continue to see using this method is excessively noisy and potentially inaccurate data.

That being said, why do you need to filter the data? What is the data being used for?

Answer 1

[Ryan G]

You could try using the smooth function.

This will smooth the data with a moving average filter. As you mentioned you only wish to observe the data, this should be adequate.

Try this as an example:

y = sin(0:0.01:10)+rand(1,1001);
yy = smooth(y);
plot(y)
hold on
plot(yy,'r')

You can see the difference.