Experimental variogram (of type vario-class) whose contents must be retrieved

Rank of the (first) target variable.

Rank of the (second) target variable. If not defined, it is set to the first variable rank.

Rank of the target direction.

If the vario-class structure contains a non-symmetric function. The the user may choose to extract:

• 0: the values for negative and positive distances

• 1: the values for positive distances only

• 2: the values for negative distances only

In any case, the distances are always turned to positive values for better legibility.