need help in iteration.

hi, can someone show me how to do a more complicated iteration process? i really need some examples.

[Geoff Hayes]

ker - what type of iteration process are you interested in? while loops, inner for loops, or something else? Please be more specific as your question is much too general.

[ker fang fang]

 xrange = 0:24;
 a= [ 1 5 15 18 10 9 6 4 12 11];
 b = (a+2*a); %function
 b;
 best = min (b);
 N=100;

 v = 0; 
 x = a; 

 for i = 1:N
    v = velocity(i);
    velocity(i+1) = 0.9*velocity(i) + 2*(0.5)*(b-a)+2*(0.5)*(best - a);
    xnew = a + velocity(i+1); 

    d = xnew + 2*xnew;
    d; 

    b1 = sum (b);
    d1 = sum(d);

    if d1>b1;
        result = a;
    else if b1>=d1;
        result = xnew; 
    end 
 end

this is the example of my code, how do i replace the new velocity value into the velocity equation?