Some issues in Simple_Kriging_Demo.xlsx

[NeoStarkX]

Hello and hope you are doing well. First I have to appreciate your efforts on providing useful resources. I was checking Simple_Kriging_Demo.xlsx file and I think I came across some errors in it. 1 - In the matrix number 4, its diagonal elements are set to fixed value 0. It has to be equal to the nugget! 2 - In the matrix number 5, I think covariance are being calculated in a wrong way because if I'm not wrong, we know that: Covariance + Variogram = Sill (spherical) but when I inspect the cell formula I find something different

I'm glad if you could help me with mentioned issues ( maybe I'm wrong )

Thanks in advance.