Issue 908: hessian of a constant function

Reported by Edson Valle, Sep 12, 2012

If user "accidentally" put a function which hessian is 
null (for example, a constant function, such as  eye(3,3)), diffcode 
returns the error:
 !--error 21 
Invalid index.

at line     151 of function diffcode_hessian called by :  

Off course that if user previously know that a function is constant, 
he won't try to get it's hessian, but in case where the user wants 
to place generic functions, I think that could be a good idea to 
place this check in the code.

Created: 6 years 4 months ago by Edson Valle

Status: New