matlab不用for循环怎么做？

Question

k=0;c=0;
for i=1:l-1
    for j=i+1:l
        k=k+1;
        distance(k)=sqrt((positionplus(i,1)-positionplus(j,1))^2+(positionplus(i,2)-positionplus(j,2))^2+(positionplus(i,3)-positionplus(j,3))^2);
        if(distance(k)>range1 && distance(k)<range2)
            c=c+1;
            a=[positionplus(i,1),positionplus(i,2),positionplus(i,3)];
            b=[positionplus(j,1),positionplus(j,2),positionplus(j,3)];
            position1(c,1)=a(1,1);position1(c,2)=a(1,2);position1(c,3)=a(1,3);
            position2(c,1)=b(1,1);position2(c,2)=b(1,2);position2(c,3)=b(1,3);
        end
    end
end