Add an element to a vector after taking difference
3 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
Christoph Meier
il 3 Set 2015
Commentato: Star Strider
il 3 Set 2015
Dear Matlab community,
I am currently running some stationarity test, for which I take log-differences. However, if stationatiry tests still suggest non-stationarity, I would have to take the second difference.
The problem obviously is, that taking another difference changes the vector size, as now some of my variables are by 1 element shorter (those with the second difference).
I would like to add a zero as the first element to those column vectors, in order to restore equal dimensions.
It would basically look like this:
A =
X
X
X
B=
0
X
X
X
Thank you very much in advance!
Chris
0 Commenti
Risposta accettata
Star Strider
il 3 Set 2015
That is easy enough to do:
B = [0; A];
However another way might be to use interp1 to artificially ‘stretch’ ‘A’:
A = randi(9, 14, 1); % Create Data: ‘A’
Ax = [1:14]'; % Independent Variable Vector For ‘A’
Bx = [1:15]'; % Independent Variable Vector For ‘B’
B = interp1(Ax, A, Bx, 'linear', 'extrap'); % Interpolate/Extrapolate To Calculate ‘B’
I offer it as an alternative.
2 Commenti
Più risposte (0)
Vedere anche
Categorie
Scopri di più su Logical in Help Center e File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!