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:
Thank you very much in advance!