Not sure how to implement specific part of Pade' Algorithm in MATLAB????

Hello,

I am implementing the Pade' algorithm in MATLAB as is specified in the book Numerical Analysis (Burden) 9th edition (heres link http://ins.sjtu.edu.cn/people/mtang/textbook.pdf) book page 531, but I am not sure how to write the code for Step 12:

Step 12 Let k be the smallest integer with i ≤ k ≤ N and bk,i = maxi≤j≤N bj,i.

(Find pivot element.)

This is all my code for the Pade Algorithm so far, help would be appreciated Thanks.

    if true
      %Determine the Padé approximation of degree 6 with n = m = 3 for f (x) = sin x. 
  %Compare the results at xi = 0.1i, for i = 0, 1, . . . , 5, 
  %with the exact results and with the results of the sixth Maclaurin polynomial.

%Step 1
n = 3;
m = 3;
N = m + n;

%Step 2 skip
A = [0,1,0,-1/6,0,1/120];
%A = ones(1,6);

%Step 3
Q = ones(1,4);
P = ones(1,4);
Q(1,1) = 1;
P(1,1) = A(1,1);

%Step 4
B = ones(N,N);
for i = 1:N
    %Step 5
    for j = 1:i-1     
        if j <= n
           B(i,j) = 0;
        end 
    end
    %Step 6
    if i <= n
        B(i,j) = 1;
    end
    %Step 7 
    temp1 = 1;
    for j = i + temp1:N
        temp1 = temp1 + 1;
        B(i,j) = 0;
    end
    %Step 8
    for j=1:i
        if j <= m
            temp2 = i-j;
            if temp2==0                 %this is not actually right 
                temp2 = 1;
            end
            B(i,n+j) = -1*A(1,temp2);
        end
    end
    %Step 9
    temp3 = 1;
    for j=n+i+temp3:N
        temp3 = temp3 + 1;
        B(i,j) = 0; 
    end
    %Step 10
    B(i,N+1) = A(1,i);
end
%Step 11
temp4 = 1;
for i = n + temp4:N-1
    temp4 = temp4 + 1;
    for
    for k=i:N
        k=min(

      %Step 13
      if B(k,i)==0
          Display('The system is singular');
          break;
      end

      %Step 14
      if k ~= i
          temp5 = 0;
          for j=i+temp5:N+1
              temp5 = temp5 + 1;
              temp6 = B(i,j);
              B(i,j) = B(k,j);
              B(k,j) = temp6;
          end
      end
      %Step 15
      temp7 = 1;
      for j=i+temp7:N
          temp7 = temp7 + 1;
          %Step 16
          xm = B(j,i) / B(i,i);
          %Step 17
          temp8 = 1;
          for k=i+temp8:N+1
              B(j,k) = B(j,k) - xm * B(i,k); %not sure about this 
          end
          %Step 18
          B(j,i) = 0;
      end

end
%Step 19
if B(N,N) == 0
    Display('The system is singular!');
    break;
end

%Step 20
if m>0
    Q(1,m) = B(N,N+1) / B(N,N);
end

%Step 21
temp9 = 1;
for i=N-temp9:n+1
    temp9 = temp9 + 1;
    Q(1,i-n) = (B(i,N+1) - shit) / (B(i,j)); %shit
end

%Step 22
temp10 = 0;
for i=n-temp10:1
    temp10 = temp10 + 1;
    P(1,i) = B(i,N+1) - shit; %shit
end

%Step 23
Display('P is');
Display(P);
Display('Q is');
Display(Q);

%DONE 

    end