  Conductivity equation is studied in piecewise smooth plane domains and with
measure-valued current patterns (Neumann boundary values). This allows one to
extend the recently introduced concept of bisweep data to piecewise smooth
domains, which yields a new partial data result for Calder\'on inverse
conductivity problem. It is also shown that bisweep data are (up to a constant
scaling factor) the Schwartz kernel of the relative Neumann-to-Dirichlet map. A
numerical method for reconstructing the supports of inclusions from discrete
bisweep data is also presented.
