[CppAD] Infinite loop in ode_err_control

[Mitch Watrous]

Hi.

I have version 20070904 of CppAD installed on my Linux machine.

 From my discussion with Brad Bell today, we believe that the following 
code from lines 508 to 513 of ode_err_control.hpp cause an infinite loop 
for my problem, which has derivatives all set equal to Not a Number (NaN):

		// check if this steps error estimate is ok
		ok = ! (hasnan(xb) || hasnan(eb));
		if( (! ok) && (step <= smin) )
		{	ef = nan_vec;
			return nan_vec;
		}


Thanks,
Mitch Watrous
RFPK
University of Washington