Putting 1 around the matrix

Hi I have a 3X3 matrix and want to put 1 around the matrix as it will become 4X4 matrix.....

[Adam]

What do you mean by 'around the matrix'? Wouldn't it become 5x5 in that case or do you mean around just one horizontal and one vertical side? If so which sides?

[Offroad Jeep]

ya sorry its 5X5

[Offroad Jeep]

yes I need 3X3 matrix Converted to 5X5 by putting 1 all around

Answer 1

[Andrei Bobrov]

Let A - your matrix [3 x 3]:

A = magic(3);
out = ones(2 + size(A));
out(2:end-1,2:end-1) = A;

[Offroad Jeep]

Thanks ..... worked

Answer 2

[Adam]

a = zeros(3);
b = padarray( a, [1 1], 1 );

would put 1s all the way round, but this produces a 5x5 matrix. A 4x4 matrix result is ambiguous without being more clearly defined.

Note: This requires the Image Processing Toolbox though

[Offroad Jeep]

worked Thanks