Sorting Vectors descending order

I appreciate if anyone could help me for writing below sorting for different vectors: Assumed :

A1= (a1,a2)
A2= (a3,a4)
A3=(a5,a6)
.
.
An= (ai, aj)

How can I sort A1, A2, … ,An. by just first member comparison descending order (1) or second comparison (2), or both member comparison (3): solution : (for example)

1)  a3>a1>a5 ---> output: A2, A1, A5...
or
2) a6>a4>a2 ----> output:  A3,A2,A1
3) a1>a3 >a5 and a2>a4 >a6  --->output: A1, A2,A3

Answer 1

[Star Strider]

The sortrows function is probably what you want. See specifically Sort Rows of a Matrix

[Omid Ameri Sianaki]

Thank you Star Strider, The out put is very important for me. I want to reach to A1, A2, A3. after sorting the matrix I can not figure out A1,A2,A3 orders. Can you help me please.

[Star Strider]

My pleasure!

Can you be a bit more specific about what A1 ... An are, and what a1, a2, ... ai, aj are? Are they individual array elements, vectors, or something else?

[Omid Ameri Sianaki]

Thank you. For example:

a=[1,5,9];
b=[2,6,10];
c=[3,7,11];
d=[4,8,12];
e=[a;d;b;c]
B=sortrows(e)

then the answer is

B =

     1     5     9
     2     6    10
     3     7    11
     4     8    12

so I want the above matrix (solution)to show me the vectors name instead of value. for above example B=[a;b;c;d] I mean I made e with vector names but I received a vector with values how can I reach to a sorted matrix with vector names?

[Star Strider]

Superb! It took some experimenting, but this seems to work:

a=[1,5,9];
b=[2,6,10];
c=[3,7,11];
d=[4,8,12];

ec = {'a' 'd' 'b' 'c'};                     % Matrix as cell array by vector name
e = cell2mat(cellfun(@eval, ec, 'uni',0)')  % Create matrix from ‘ec’
[B,I] = sortrows(e)                         % Sort rows
vn = ec(I)                                  % Sorted vector names

I created a cell array of the vector names in ‘ec’ in the order you want them in matrix ‘e’. I then created matrix ‘e’ by evaluating the cell array in the order you specified, using cellfun and then creating a numerical matrix from it with cell2mat. I then sorted ‘e’ with sortrows, and used the index vector ‘I’ to create the sorted array names in ‘vn’.

My code produces:

e =

       1     5     9
       4     8    12
       2     6    10
       3     7    11

B =

       1     5     9
       2     6    10
       3     7    11
       4     8    12

I =

       1
       3
       4
       2

vn = 

      'a'    'b'    'c'    'd'

Is that what you want?

[Omid Ameri Sianaki]

Awesome! Perfect Answer. Thank you very much. Yes it was what I wanted and I appreciate for your time.

[Star Strider]

My pleasure!

That was a really fun problem for me!