+function g = rosenbrock_gradient1(x)
+ ##
+ ## A version of the rosenbrock_gradient() function which takes a
+ ## column 2-vector instead of two distinct arguments. See
+ ## rosenbrock_gradient.m for more information.
+ ##
+ if (length(x) == 2)
+ g = rosenbrock_gradient(x(1), x(2));
+ else
+ g = NA;
+ end
+end