Evaluation of Pressure Tensor in Constant-Volume Simulations of Hard and   Soft Convex Bodies
  A method for calculating the pressure tensor in constant-volume Monte Carlo simulations of convex bodies is presented. In contrast to other approaches, the method requires only an isotropic scaling of the simulation box, and the counting of simple geometric quantities characterizing overlapping pairs. Non-sphericity presents no special difficulties. The result is expressed as a sum of pairwise contributions, and can therefore be used to compute pressure tensor profiles in a conventional way. 
Michael P. Allen