LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

LabVIEW Derivative x(t).vi

Hello All,

 

I'm trying to interpret the output from the Derivative x(t).vi and want to make sure I'm doing so appropriately.  The default value for the "dt" input is 1.0.  I have force plate data that are sampled at 1200Hz.  I interpret this to mean that the value of 1.0 for "dt" represents a real time interval of 0.833ms [(1200pts/1s) x (1s/1000ms) = 0.833ms/pt] and that the units of the derivative (i.e. loading rate = change in force/unit time) will be in N/0.833 ms.  I would then need to convert this to N/s by multiplying by 1000ms/1s. 

 

can anyone confirm (or deny!) this?  Thanks for the help.    

0 Kudos
Message 1 of 3
(3,343 Views)

Yes, it is correct.

Interval is constant so it simply divides differences (dx = dN array) by interval (dt = 0.833 ms = 0.000833 s)

BTW, you can verify it if you input x = [1 2 3] and check how result depends on dt... 

0 Kudos
Message 2 of 3
(3,323 Views)

Excellent - thanks so much for your help!

0 Kudos
Message 3 of 3
(3,282 Views)