Increasing size of Multidimensional Array

Hi all,

I have one multidimensional array T of size (n1,n2,n3,...) and I need to build a new array S of size (n1+1,n2+1,n3+1,...) with the same values of A and zeros in all the added coefficients. In other words, I need to pad one "slice" of zeros at the end of each dimension of T.

The problem is that I don't know the size of T until runtime... so code should work for any number of dimensions...

Any idea how to do it? (other than a extremely slow loop in all coefficients of A) Thanks in advance! Sergio

[teresa]

Ok, this is my code. Any improvement/correction will be welcomed.

si = size(T);
nd = ndims(T);

ix = cell(nd,1);
for d = 1:nd
  ix{d} = 1:si(d);
end         

A = zeros(si+1);
A(ix{:}) = T;

[Azzi Abdelmalek]

Usuaris, have you looked at the two answers?

[teresa]

I haven't! sorry.

Your solution is more simple than mine. Thanks for your answer.

Answer 1

[Azzi Abdelmalek]

idx=num2cell(size(T)+1);
T(idx{:})=0;

[Stephen23]

Very tidy solution. To answer the original question first assign T to a new array S:

S = T;
X = num2cell(1+size(S));
S(X{:}) = 0;

[Guillaume]

Indeed! Much simpler (and faster) than mine.

Answer 2

[Guillaume]

newT = zeros(size(T) + 1); %create new array with increased size
destidx = arrayfun(@(s) 1:s, size(T), 'UniformOutput', false);
newT(destidx{:}) = T

The last line is the programmatic equivalent of

newT(1:size(T, 1), 1:size(T, 2), 1:size(T, 3), ...) = T

And the line before that is just building these indices