Question about the **_steadystate.m function part

I notice that at the beginning of the _steadystate.m there are at least three forms: 1. function [ys,check] = **_steadystate(ys,exo). 2. function [ys,check] = **_steadystate(ys,exe). 3. function [ys,check] = **_steadystate(junk,ys). Could anyone tell me what do these mean by ‘exo’, ‘exe’ and ‘junk’. Are there any more parameters? Where can I get the reference?
Thank you.

What file(s) are you referring to? There is no difference between 1 and 2 except the name of the second argument (which is not a problem if the content of the routine is defined accordingly). The third case is more problematic. Look here, and also in the example folder the file NK_baseline_steadystate.m.


Only the first two make sense and are valid in Dynare. @stepan-a linked to a proper example file. Note that that function is used for a stochastic model where the exo argument is not used. What that input does is providing the value of the exogenous variables at which the steady state is computed. You need this in perfect foresight models if you have permanent shocks and therefore different steady state values at the beginning and end. See e.g. Permanent Shock in deterministic model

Thanks for two, that’s pretty clear.