search for string array index

I have a very big string array to search but it is in this format:

x=['a b c0  d';
   'a b e1  f';
   'a x d1  f';]

how can i efficiently search for the row index which has the letter 'a' in position 1 and the letter 'e1' in position 5:6. In this case the index is 2

Thanks. -S

Answer 1

[Matt Fig]

That example fails...

But let's try this one:

x=['a b c0 d';'a b e1 f';'a x d2 f';'m b e1 f';'a b e1 f'];
find(x(:,1)=='a' & x(:,5)=='e' & x(:,6)=='1')

[Sam]

sorry just correct the example Thanks Matt

[Matt Fig]

See my example, and solution.