% get_370_leads.m
% challenge ECGs
% 20091026; A. van Oosterom
clear
% http://www.physionet.org/challenge/2007/data:
% Geometry: Dalhousie lead system:
% Electrode Location 120 Leads.pdf
% Torso 352 Nodes.pdf
siglabels=loadmat('elnodes_120_352.lst'); % nodes among the 352 nodes Dalhousie grid where potentials have been recorded
sigfile='ecgs_case3.asc';
PHI=loadmat(sigfile); % original data matrix; first three columns do not relate to potentials
% next three columns are potentials VR, VL, VF
% remaining ones: 120 potentials recorded at the nodes: siglabels of the Dalhausie grid
PHI=PHI'; % personal preference
PHI=PHI([(4:6)'; siglabels+6],:); % extracts recorded data only: 123 leads
PHI=PHI/1000; % conversion to mV
T=loadmat('transfer_370_123.mat');
% T=intripol(VER,ITRI,elnodes);
% savemat('transfer_370_123.mat',T);
PSI=T*PHI; % potentials at all 370 nodes of the thorax geometry defined at:
% " Detailed heart, lung and torso geometry ..."
elnodes =loadmat('elnodes_123_370.lst'); % labels of the vertices
% of the thorax geometry where signals have been recorded