That is one way to do it (although this is not log percentage deviations, but rather actual percentage deviations; but at first order, there is no difference)
More generally, see Question about understanding irfs in dynare
That is one way to do it (although this is not log percentage deviations, but rather actual percentage deviations; but at first order, there is no difference)
More generally, see Question about understanding irfs in dynare