Integrating functions with with constant arguments

[John Dalton]

QUESTION 1:

I'm trying to run the following function under octave:

function z = test_handle(t)
   z   = quad(@(x) pow2(x, t), 0.5, 1);
end

It is an integration with a constant argument in the integrand function.
It works in Matlab, but octave 2.1.73 fails with the
following error. 

error: `t' undefined

According to this post: 
http://velveeta.che.wisc.edu/octave/lists/archive//octave-maintainers.2002/msg00110.html
it should work.  I've also tried making 't' global ("global t") and
also tried using a global intermediate variable between the argument t
and its use as a  parameter to pow2.  If pow2 is replaced with a user
defined function (say fun2) the code fails saying "fun2" is not
defined.  It's as if the evaluation of quad's argument function is
not seeing the parent's environment.

QUESTION 2:

As an aside, I also did the following test:

octave:5> global a=3;is_global('a')
ans = 0

I would have though the answer should be '1'.


Sorry if these are FAQs.  I have spent a day looking for an
answer but have not found one (apart from the email above).
Any help will be appreciated very much. (Thanks in advance.)

Regards
John Dalton