gltr_control_type structure

    struct gltr_control_type{T}
      f_indexing::Bool
      error::Int32
      out::Int32
      print_level::Int32
      itmax::Int32
      Lanczos_itmax::Int32
      extra_vectors::Int32
      ritz_printout_device::Int32
      stop_relative::T
      stop_absolute::T
      fraction_opt::T
      f_min::T
      rminvr_zero::T
      f_0::T
      unitm::Bool
      steihaug_toint::Bool
      boundary::Bool
      equality_problem::Bool
      space_critical::Bool
      deallocate_error_fatal::Bool
      print_ritz_values::Bool
      ritz_file_name::NTuple{31,Cchar}
      prefix::NTuple{31,Cchar}

detailed documentation

control derived type as a Julia structure

components

Bool f_indexing

use C or Fortran sparse matrix indexing

Int32 error

error and warning diagnostics occur on stream error

Int32 out

general output occurs on stream out

Int32 print_level

the level of output required is specified by print_level

Int32 itmax

the maximum number of iterations allowed (-ve = no bound)

Int32 Lanczos_itmax

the maximum number of iterations allowed once the boundary has been encountered (-ve = no bound)

Int32 extra_vectors

the number of extra work vectors of length n used

Int32 ritz_printout_device

the unit number for writing debug Ritz values

T stop_relative

the iteration stops successfully when the gradient in the M(inverse) nor is smaller than max( stop_relative * initial M(inverse) gradient norm, stop_absolute )

T stop_absolute

see stop_relative

T fraction_opt

an estimate of the solution that gives at least .fraction_opt times the optimal objective value will be found

T f_min

the iteration stops if the objective-function value is lower than f_min

T rminvr_zero

the smallest value that the square of the M norm of the gradient of the the objective may be before it is considered to be zero

T f_0

the constant term, \(f_0\), in the objective function

Bool unitm

is \(M\) the identity matrix ?

Bool steihaug_toint

should the iteration stop when the Trust-region is first encountered ?

Bool boundary

is the solution thought to lie on the constraint boundary ?

Bool equality_problem

is the solution required to lie on the constraint boundary ?

Bool space_critical

if .space_critical true, every effort will be made to use as little space as possible. This may result in longer computation time

Bool deallocate_error_fatal

if .deallocate_error_fatal is true, any array/pointer deallocation error will terminate execution. Otherwise, computation will continue

Bool print_ritz_values

should the Ritz values be written to the debug stream?

char ritz_file_name[31]

name of debug file containing the Ritz values

NTuple{31,Cchar} prefix

all output lines will be prefixed by .prefix(2:LEN(TRIM(.prefix))-1) where .prefix contains the required string enclosed in quotes, e.g. “string” or ‘string’