Jump part of a BV derivative ($D^{j}u=(u^{+}-u^{-}){\nu }_u{\mathcal{H}}^{n-1}\lfloor J_u$)

This derivative component is carried by the jump set of a BV function. Swapping the two BV traces on a hypersurface and reversing the normal leaves it unchanged. In one dimension it consists of the point measure atoms, each weighted by the difference between the right and left limits.