This question may be for @cheng : I would like to have clarifications regarding calculation of H inside FLAC3D, specifically:
(1) H = H0 + Hypsi, or H = H0 - Hypsi (which is used in VBA of Mike)
(2) Have FLAC3D applied any cut-off to H? It looks like FLAC3D accepts negative value of H?

(1) This is a typo in the documentation. It should be â€śminusâ€ť. The code is using â€śminusâ€ť.
(2) Although it accepts a negative H. The cut-off is 10 and 0.5/(lambda-kappa), whichever is larger.
We will update the doc. Sorry for the inconvenience.