sign of a permutation (1 for even, -1 for odd)
0001 function s = sign(p) 0002 % sign of a permutation (1 for even, -1 for odd) 0003 n = length(p); 0004 if (n==0) 0005 s = 1; 0006 return 0007 end 0008 0009 c = cycles(p); 0010 s = 0; 0011 for k=1:length(c) 0012 s = s + length(c{k}) + 1; 0013 end 0014 0015 s = mod(s,2); 0016 s = (-1)^s;