binvec216vec.m

本程序利用改进的CHOW算法

function b=binvec216vec(a)
%pass a binary vector the result is a 16 vector b(0,1,2,3,...,15)
%if a's length is odd, adds a zero at the first of a
%written by Joe Williams, Stanford University
%if you use this, give author proper credit

if mod(length(a),4)==0
b=zeros(1,length(a)/4);
for c=1:4:length(a)
b(ceil(c/4))=8*a(c)+4*a(c+1)+2*a(c+2)+a(c+3);
end

else 
if mod(length(a),4)==3
b=zeros(1,(length(a)+1)/4);
elseif mod(length(a),4)==2
b=zeros(1,(length(a)+2)/4);
elseif mod(length(a),4)==1
b=zeros(1,(length(a)+3)/4);
end
b(1)=a(1);
for c=2:2:length(a)
b(c/2+1)=2*a(c)+a(c+1);
end
end