An objective list contains an objective value, a gradient, and a Hessian matrix.
Objective lists can contain additional numeric attributes that are preserved or combined with the corresponding attributes of another objective list when both are added by the "+" operator, see sumobjlist.
Objective lists are returned by objective functions as being generated by normL2, constraintL2, priorL2 and datapointL2.
objlist(value, gradient, hessian)numeric of length 1
named numeric
matrix with rownames and colnames according to gradient names
Object of class objlist