Sort a matrix based on one row?

lets say we have a 3x3 matrix as

a= 2 5 3;
   2 8 1;
   4 1 9;

and I want this matrix sorted based on its 2nd row in ascending order i.e.

     answer= 3 2 5;
             1 2 8;
             9 4 1;

Thank you for any help you can offer.

Answer 1

[Walter Roberson]

[temp, order] = sort(a(2,:));
answer = a(:,order);