Value dependant sort of matrix rows

Hi,

I have a integer matrix which I know each row contain a certain value.

I would like to sort each row of that matrix in the way this value will always be in front / first position of the row.

The other values order doesn't matter.

For example with a constant value equal to 8 :

M8 = [7 8 5;...
      8 7 3;...
      4 8 3;...
      5 8 4];

I would like in return of such a function

  sorted_M8 = [8 7 5;...
               8 7 3;...
               8 4 3;...
               8 5 4];

What is the quickest way to do this in Matlab ?

Thank you, best.

Nicolas

Answer 1

[David Hill]

sorted_M8=M8';
sorted_M8(ismember(M8',8))=M8(:,1);
sorted_M8=sorted_M8';
sorted_M8(:,1)=8;

[Nicolas Douillet]

Ok, pretty good, thank you. I also had a similar solution :

 Mt = M8';
 f = Mt ~= 8;
 M8 = Mt(f(:));
 M8 = cat(2,8*ones(size(Mt,2),1),reshape(M8,[2,size(Mt,2)])'); % 2 because I forgot to say size(T,2) = 3 always

but still keeping the hope this could be done in one single line of code.

[David Hill]

Two lines.

sorted_M8=ismember(M8,8).*M8(:,1)+~ismember(M8,8).*M8;
sorted_M8(:,1)=8;

[Nicolas Douillet]

Yeah good, thanks again. The only thing I try to avoid in general is to mix logical class objects with double class objects in computation.