// Gradient absolute value
for(std::size_t i=1;i<derivate_second_order.size();i++)
- gradient_absolute.push_back(fabs(derivate_second_order[i]-derivate_second_order[i-1])) ;
+ gradient_absolute.push_back(abs(derivate_second_order[i]-derivate_second_order[i-1])) ;
if(derivate_second_order.empty())
continue;
for(std::size_t i=1;i<derivate_second_order.size()-1;i++)