one-by-one matrix assignment

I need to find the minimum values in each column of matrix "A", and then replace those min values with the values in last row of matrix "B" (which has same number of columns). Like I have these:

>> A = randi(10,10,5)

A =

       3     5     9     5     8
       7     6     4    10     2
       8     4     1     7     4
       4     7     2     8     2
       7     5     8     7     5
       3     7    10    10     1
       5     7     8     5     7
       8     3     8     2     3
       6    10     2     1    10
       3     7     6     7     2

>> B = randi(100,3,5)

B =

      10    34    66    18    62
      99    95    49    54    81
      52     1    52     9    95

>> [M,I] = min(A)

    M =

         3     3     1     1     1

    I =

         1     8     3     9     6

And I want to replace the values of "M" with "B(end,:), so that:

A(1,1) = B(end,1);
A(8,2) = B(end,2);
A(3,3) = B(end,3);
A(9,4) = B(end,4);
A(6,5) = B(end,5);

I try "A(I) = B(end,:)" and "A(I(1,:)) = B(end,:)" but they do not work! Any ideas how I could do that? My real matrices are huge (1200x100000) so no way to do it by hand!

[Jos (10584)]

So, only the last line of B is relevant?

[Antonio]

@Jos(10584) Not really, I'm just providing a simple example! In reality I have a loop in which mateix B updates each time and I have to call a certain row of it. But that's fine, I know how to do that part, I just need to know how to do that sort of one-by-one assignment that I asked!

[Jos (10584)]

ok. then Andrei's answer suffices.

[Antonio]

@Jos (10584) great, thanks!

Answer 1

[Andrei Bobrov]

[~,idx] = min(A);
s = size(A);
A(sub2ind(s,idx,1:s(2))) = B(end,:);