Node:Multimin Stopping Criteria, Next:Multimin Algorithms, Previous:Multimin Iteration, Up:Multidimensional Minimization
A minimization procedure should stop when one of the following conditions is true:
The handling of these conditions is under user control. The functions below allow the user to test the precision of the current result.
int gsl_multimin_test_gradient (const gsl_vector * g, double epsabs)  Function 
This function tests the norm of the gradient g against the
absolute tolerance epsabs. The gradient of a multidimensional
function goes to zero at a minimum. The test returns GSL_SUCCESS
if the following condition is achieved,
and returns 
int gsl_multimin_test_size (const double size, double epsabs)  Function 
This function tests the minimizer specific characteristic
size (if applicable to the used minimizer) against absolute tolerance epsabs.
The test returns GSL_SUCCESS if the size is smaller than tolerance,
otherwise GSL_CONTINUE is returned.
