Dynamic Deviation

[nigeltorque]

Hi everybody..

i am trying to calculate the dynamic deviation of a generic signal s(t); this means i have to calculate the s(t) and the s(t + "delta"t) and the s(t - "delta"t) value of the signal as explain in the following formula:

where "p" and "delta tau" are well-know parameters.

I try to use the GET XY VALUE vi but it isn't good!

Has anyone an idea??

Thank you in advance!