MATLAB Answers

0

Calculate difference between two signals

Asked by Nimish Iwale on 17 Jul 2019
Latest activity Answered by Star Strider
on 17 Jul 2019
What and how would be the best way to calculate the difference between the 2 signals (A and B) shown below in terms of percentage difference or a factor of comparison?
Q&A.JPG

  0 Comments

Sign in to comment.

1 Answer

Answer by Star Strider
on 17 Jul 2019

I would compare them by noting that the amplitudes of the peaks vary with respect to the independent variable, similarly for both ‘A’ and ‘B’. One way would be to do a simple linear regression of one against the other:
P = [A(:) ones(size(A(:)))] \ B(:) % P(1) = Slope, P(2) = Intercept
another would be to regress both of them with respect to the independent variable (assumed here to be ‘x’):
Pa = [x(:) ones(size(x(:)))] \ A(:) % Pa(1) = Slope, Pa(2) = Intercept
Pb = [x(:) ones(size(x(:)))] \ B(:) % Pb(1) = Slope, Pb(2) = Intercept
A direct point-by-point difference or a single statistic (for example mean of the difference between them) would not capture their both changing over the independent variable at different rates, and with respect to each other.

  0 Comments

Sign in to comment.