sort an array and store them into subarrays

Hi, I have a question regarding sorting arrary and store them into subset. How can I sort an array according to the second column value and store them into subarrays. and get the value of second column. So for an arrary like the following, I would know there are 3 groups(1,2,3) according column 2 and I would get 3 subsets. Thanks a lot.

if true
1  1  9999.69307  3.374E-28
1  1  9999.72441  4.662E-27
1  2  9999.73112  2.083E-29
1  2  9999.93918  4.851E-29
1  1  9999.95707  1.353E-26
1  3  9999.69307  3.374E-28
1  1  9999.72441  4.662E-27
1  2  9999.74112  2.083E-29
1  3  9999.98918  4.851E-29
1  1  9999.99707  1.353E-26  end

Answer 1

[Azzi Abdelmalek]

A = [ 1  1  9999.69307  3.374E-28
        1  1  9999.72441  4.662E-27
        1  9  9999.73112  2.083E-29
        1  9  9999.93918  4.851E-29
        1  1  9999.95707  1.353E-26
        1  3  9999.69307  3.374E-28
        1  5  9999.72441  4.662E-27
        1  2  9999.74112  2.083E-29
        1  3  9999.98918  4.851E-29
        1  3  9999.99707  1.353E-26];
B=sortrows(A,2); % Sort A according to second column;
out=accumarray(A(:,2),(1:size(A,1))',[],@(x){A(x,:)})
out(cellfun(@isempty,out))=[]

[Chong Tao]

Thank you Azzi. This works perfect.

Answer 2

[Chong Tao]

Thank you very much Azzi and Per isakson! I need to clarify my question. I'm trying to load a pretty big array from file(3000X10 array) and sort the array. the second column may not be consective numbers as in previous sample. It can be any number from 1 to 11 and can't be predicted unless the data was loaded. say for example,

if true
    A = [ 1  1  9999.69307  3.374E-28
          1  1  9999.72441  4.662E-27
          1  9  9999.73112  2.083E-29
          1  9  9999.93918  4.851E-29
          1  1  9999.95707  1.353E-26
          1  3  9999.69307  3.374E-28
          1  5  9999.72441  4.662E-27
          1  2  9999.74112  2.083E-29
          1  3  9999.98918  4.851E-29
          1  3  9999.99707  1.353E-26];
end

[Chong Tao]

all these are double precision numbers. is that what you ask?

Answer 3

[Jos (10584)]

Shorter, with less overhead and more flexible:

[~,~,j] = unique(A(:,2))
C = accumarray(j,1:numel(j),[max(j) 1],@(k) {A(k,:)})