array assignment question

I have this code:

a = zeros(4, 5);
b = ones(2, 4);
[rows columns] = size(b);
% Define upper left of where I want to place array b
leftColumn = 1;
topRow = 3;
% Do the assignment to place it there.
a(topRow:topRow+rows-1, leftcolumn:leftColumn-columns-1) = b;

disp(a)

How can I change it to define the right Column and not the left? I tried many changes but I have not found it yet! Thank you..

Answer 1

[Matt Tearle]

So, this is what you want?

a = zeros(4, 5);
b = ones(2, 4);
[rows columns] = size(b);
% Define upper left of where I want to place array b
rightColumn = 4;
topRow = 3;
% Do the assignment to place it there.
a(topRow:(topRow+rows-1), (rightColumn-columns+1):rightColumn) = b;

disp(a)

Or do you want the columns of b flipped? In which case, just replace = b; with = fliplr(b);

[athpapa -]

thank you very much!!This is what I want...

Answer 2

[Rob Graessle]

So you just want to flip the horizontal orientation of b before you insert it into the same location in a?

a(topRow:topRow+rows-1, leftColumn:leftColumn+columns-1) = fliplr(b);

Is that what you want?

Answer 3

[Oleg Komarov]

I assume you wanted to do:

A = zeros(4, 5); 
B = ones(2, 4); 
szA = size(A);
szB = size(B);

% Align to top left
A(1:szB(1),1:szB(2)) = B
A =
     1     1     1     1     0
     1     1     1     1     0
     0     0     0     0     0
     0     0     0     0     0

% Align to top right
A(1:szB(1), 1 + szA(2)-szB(2):end) = B
A =
     0     1     1     1     1
     0     1     1     1     1
     0     0     0     0     0
     0     0     0     0     0

EDIT #1

If you want to keep exactly your code:

a = zeros(4, 5);
b = ones(2, 4);
[rows columns] = size(b);
% Define upper left of where I want to place array b
leftColumn = 2;
topRow = 3;
% Do the assignment to place it there.
a(topRow:topRow+rows-1, leftColumn:leftColumn+columns-1) = b;

disp(a)

I just changed leftColumn to 2.

Oleg

[athpapa -]

Not exactly. I want with the code that I have to put the table b in the same place as the above code but to start from right to left and not from left to right!If you know how can I do that, you would help me a lot!I have a mistake on my code, the right is:a(topRow:topRow+rows-1, leftColumn:leftColumn+columns-1) = b;

This code put the b table from left to right into the a table. I want the opposite, from right to left, in the same place of the a table!