what is wrong?

why it show error

??? Error using ==> cat CAT arguments dimensions are not consistent.

Error in ==> @(i)cat(3,randperm(m)',[11*ones(N(1,i),1);22*ones(N(2,i),1);33*ones(N(3,i),1);44*ones(N(4,i),1)])

m=22;

AA = [m 7];

N=[11,9,11,10,10,9,9;7,7,7,7,7,7,7;4,5,4,4,4,5,5;1,1,1,1,1,1,1];

B = cell2mat(arrayfun(@(i)cat(3,randperm(m)',[11*ones(N(1,i),1);22*ones(N(2,i),1);33*ones(N(3,i),1);44*ones(N(4,i),1)]),1:size(N,2),'un',0));
x = B(sub2ind(szAA,B(:,:,1),cumsum(ones(AA),2))+prod(AA));

i cant understand what the problem,can someone help me?

[Sean de Wolski]

I don't know but that equation above is painful on the eyes.

Answer 1

[Andrei Bobrov]

Hi Sahab! More variant solving your problem

m=22;
AA = [m 7];
N=[11,9,11,10,10,9,9;7,7,7,7,7,7,7;4,5,4,4,4,5,5;1,1,1,1,1,1,1];

t=sum(N)~=AA(1);
if any(t), I1 = randi(size(N,1)-1); N(I1,:) = N(I1,:)-t; end
x = zeros(AA);
xx = 11*(1:4)';
for j = 1:size(N,2)
    x(randperm(AA(1)),j) = ...
            cell2mat(arrayfun(@(i)xx(i)*ones(N(i,j),1),1:length(xx),'un',0).');
end

[Sahab]

thanks andrei, this is what i need.. :D

Answer 2

[Matt Fig]

The problem is that in your first N, all of the values sum to m:

m=22;
N=[8,11,18,7,9,8,13;6,2,1,5,3,6,1;4,3,2,5,5,4,6;4,6,1,5,5,4,2];
all(sum(N)==m)

and the second does not.

N=[11,9,11,10,10,9,9;7,7,7,7,7,7,7;4,5,4,4,4,5,5;1,1,1,1,1,1,1];
all(sum(N)==m)

In order to get away from the CAT error, you need all(sum(N)==m) to return true.

[Sahab]

thanks for the replied Matt Fig. this help me too,but andrei bobrov solution is what i need.

Answer 3

[Andy]

When you cat along the third dimension, the first two dimensions must match up. Let's look at what your cat-ing. First, you have randperm(m)', a column vector of size [m 1], where m is always 22. Then you have

[11*ones(N(1,i),1);22*ones(N(2,i),1);33*ones(N(3,i),1);44*ones(N(4,i),1)]

For, say, i=1, this has size [N(1,1)+N(2,1)+N(3,1)+N(4,1), 1]. This is a column vector of length 23 (and the length will be different depending on i). So the dimensions don't match up correctly.

What are you really trying to do with this code?

[Sahab]

when i change the value of N=[8,11,18,7,9,8,13;6,2,1,5,3,6,1;4,3,2,5,5,4,6;4,6,1,5,5,4,2]

it show no error..why i cant use N=[11,9,11,10,10,9,9;7,7,7,7,7,7,7;4,5,4,4,4,5,5;1,1,1,1,1,1,1];

what should i change?

[Andy]

Matt Fig responded correctly in his answer below, except I think he intended:

all(sum(N) == m)

rather than

all(sum(N)) == m

It is either an accident that one of your values of N satisfies this constraint (which MUST be satisfied for the cat to work), or the N which does not work was incorrectly calculated somehow. Again, could you describe what your code is supposed to accomplish? How is N calculated? What are B and x ultimately supposed to hold? Can you give a small example of some input and the desired output?