Set the values in this set to the indexing values of
the passed DataFrame.The number of indexing columns of the
parameter must be equal to the arity of this set instance.
For example, considering the following AMPL entities and corresponding
objects:
set A := 1..2;
param p { i in A } := i+10;
set AA;
The following is valid:
Set A = ampl.GetSet("A");
Set AA = ampl.GetSet("AA");
AA.SetValues(A.GetValues()); // A has now the members {1, 2}
public void SetValues(DataFrame df)