Hi Everyone,

I want to regularize the pilot points using Tikhonov Regularization based on using co-variance matrix only without any preferred values or differences as shown in the attached figure. Every time I am applying this, the Pest check returns an error message that is saying "[b]If PEST is run in regularisation mode then at least one observation group must be a regularisation group; that is, the first five letters of the  name of at least one group must be "regul"[/b], and I am not even able to change the obs group names as they are linked to obs definition. So is there anyway to just adapt the spatial correlation between the values as a regularization way without any preferred values or differences?? thanks