matrix, using variables like a1,a2,a3,...an, minimum

how to take matrix element (i.e row) one by one and save each new matrices in a new variable

example:

original matrix: a=[2 6 7 8;4 5 3 7;9 7 6 9;5 3 1 9]

become: a1=[4 5 3 7;9 7 6 9;5 3 1 9] a2=[2 6 7 8;9 7 6 9;5 3 1 9] a3=[2 6 7 8;4 5 3 7;5 3 1 9] a4=[2 6 7 8;4 5 3 7;9 7 6 9]

then i want to find determinant from each of them * their transpose (ie: det(a1*a1')) and then find which one of them has minimum value

i have asked before and i receive this answer

a=[2 6 7 8;4 5 3 7;9 7 6 9;5 3 1 9]
id = ~eye(size(a));
s = size(a,2);
h = zeros(s*[1 1 1] - [1 0 0]);
kt = zeros(s,1);
for j1 = 1:s
    k = a(id(:,j1),:);
    kt(j1) = det(k*k.');
    h(:,:,j1) = k;
end
[out,outidx] = min(kt)

the problem is i don't know how this code works, and since the matrix i am going to use is different than that i use as example, i can't adjust that code

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F

[eri]

yes i already read it, but i still don't get it

Answer 2

[N/A]

eval( sprintf( 'a%d=a(%d, :), ', [1;1]*(1:size(a,1))) )

Answer 3

[carmen]

ok heres a brute force version without fancy commands.

a=[2 6 7 8;4 5 3 7;9 7 6 9;5 3 1 9]

rows=size(a,1);
columns=size(a,2);

for i=1:rows
    b=1:rows;
    b(i)=[];
    tmp=a([b],:)
    eval(sprintf('a%d=tmp;',i));
    determinante(i)=det(tmp*tmp');
end
min=find(determinante==min(determinante)); %gives you the index of 
% determinante where the minimum values is found

i hope this works for arbitrary n*m matrices

[carmen]

add a

determinante(min)

to see what the minimum value is