Visually, it looks like 0.3 is in T
But find() says it is not there.
Is it there? Let's look at the bit representation
fprintf('a:\n'); arrayfun(@pX, a);
So for the literal, the bit representation ends in all hex 3's.
Is that bit representation present in T?
fprintf('\nT:\n'); arrayfun(@pX, T);
No. There is a very similar bit representation that ends in a 4 rather than a 3. The last 4 bits of the actual value are 0011 (decimal 3), but the closest that T has is something for which the last 4 bits are 0100 (decimal 4).
When you calculate something two different ways, the bits are not necessarily going to come out identical.
fprintf('%016X\n', typecast(N, 'uint64'));