Matlab arrays operation

Question

I have an array to order it as stated in the other array (the second array is the indices that i want the first array to be ordered in )

if a=[2 3 1 8 7]
   q=[2 5 1 4 3]
then 
   a=[3 7 2 8 1]

Answer 1

You can use the second array to index into the first:

a = a(q);