A system for determining a site of origin of a natural electrical pulse in a living body comprising: a plurality of electrical sensors for positioning at a corresponding plurality of locations on a surface of a living body; and a computer system configured to: determine a first vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on a surface of a living body due to a natural electrical pulse, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; determine a different vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on the surface of the living body due to each stimulated signal of a plurality of stimulated signals within the living body, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; receive stimulated position data that indicates a different corresponding position within the living body where each of the plurality of stimulated signals originates; and determine the site of origin of the natural electrical pulse based on the first vector and a plurality of different vectors and the stimulated position data, wherein determining the site of origin of the natural electrical pulse further comprises determining a single vector transform that best converts every different vector to the different corresponding position within the body or determining a linear combination of the different vectors to produce the first vector. a plurality of electrical sensors for positioning at a corresponding plurality of locations on a surface of a living body; and a computer system configured to: determine a first vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on a surface of a living body due to a natural electrical pulse, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; determine a different vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on the surface of the living body due to each stimulated signal of a plurality of stimulated signals within the living body, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; receive stimulated position data that indicates a different corresponding position within the living body where each of the plurality of stimulated signals originates; and determine the site of origin of the natural electrical pulse based on the first vector and a plurality of different vectors and the stimulated position data, wherein determining the site of origin of the natural electrical pulse further comprises determining a single vector transform that best converts every different vector to the different corresponding position within the body or determining a linear combination of the different vectors to produce the first vector. determine a first vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on a surface of a living body due to a natural electrical pulse, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; determine a different vector of temporal changes in electrical data measured at the plurality of electrical sensors positioned at the corresponding plurality of locations on the surface of the living body due to each stimulated signal of a plurality of stimulated signals within the living body, wherein each vector comprises a plurality of elements based on a plurality of statistics of the temporal changes at each electrical sensor; receive stimulated position data that indicates a different corresponding position within the living body where each of the plurality of stimulated signals originates; and determine the site of origin of the natural electrical pulse based on the first vector and a plurality of different vectors and the stimulated position data, wherein determining the site of origin of the natural electrical pulse further comprises determining a single vector transform that best converts every different vector to the different corresponding position within the body or determining a linear combination of the different vectors to produce the first vector.