#$%^&*AU2013231218B220180405.pdf#####ABSTRACT A method for forming an electropotential map, including: measuring locations of points on a surface of a body organ, and measuring electrical potentials of a subset of the points. The method further includes assigning respective resistances to line segments joining the points so as to define a resistor mesh, and generating an electropotential map of the surface by applying an harmonic function to the resistor mesh responsive to the measured electrical potentials.01 (D:: - U 0) C U (D U L z D r U) 0