Method for scaling the linear system.
Determines the method used to compute symmetric
scaling factors for the augmented system (see
also the "linear_scaling_on_demand" option).
This scaling is independent of the NLP problem
scaling. By default, MC19 is only used if MA27
or MA57 are selected as linear solvers. This
value is only available if Ipopt has been
compiled with MC19.
The default value for this string option is "mc19".
- none: no scaling will be performed
- mc19: use the Harwell routine MC19
- slack-based: use the slack values