coupling {<coupling-statement>} end
<coupling-statement> :==
class=<classname>
Starts a new class which applies to all assignment, coefficent,
force, and potential entries until another class entry is issued.
cv=<integer>
Select partition number for cross-validation.
force <real> [<real>]
Force constant(s) for all assignments in the current class.
Default = 50 [10].
nrestraints=<integer>
Number of slots for J coupling restraints to allocate in memory.
Default = 200.
reset
Erase the J coupling assignment table, but keeps nrestraints the same.