lsqp_control_type structure#

#include <galahad_lsqp.h>

struct lsqp_control_type {
    // components

    bool f_indexing;
    ipc_ error;
    ipc_ out;
    ipc_ print_level;
    ipc_ start_print;
    ipc_ stop_print;
    ipc_ maxit;
    ipc_ factor;
    ipc_ max_col;
    ipc_ indmin;
    ipc_ valmin;
    ipc_ itref_max;
    ipc_ infeas_max;
    ipc_ muzero_fixed;
    ipc_ restore_problem;
    ipc_ indicator_type;
    ipc_ extrapolate;
    ipc_ path_history;
    ipc_ path_derivatives;
    ipc_ fit_order;
    ipc_ sif_file_device;
    rpc_ infinity;
    rpc_ stop_p;
    rpc_ stop_d;
    rpc_ stop_c;
    rpc_ prfeas;
    rpc_ dufeas;
    rpc_ muzero;
    rpc_ reduce_infeas;
    rpc_ potential_unbounded;
    rpc_ pivot_tol;
    rpc_ pivot_tol_for_dependencies;
    rpc_ zero_pivot;
    rpc_ identical_bounds_tol;
    rpc_ mu_min;
    rpc_ indicator_tol_p;
    rpc_ indicator_tol_pd;
    rpc_ indicator_tol_tapia;
    rpc_ cpu_time_limit;
    rpc_ clock_time_limit;
    bool remove_dependencies;
    bool treat_zero_bounds_as_general;
    bool just_feasible;
    bool getdua;
    bool puiseux;
    bool feasol;
    bool balance_initial_complentarity;
    bool use_corrector;
    bool array_syntax_worse_than_do_loop;
    bool space_critical;
    bool deallocate_error_fatal;
    bool generate_sif_file;
    char sif_file_name[31];
    char prefix[31];
    struct fdc_control_type fdc_control;
    struct sbls_control_type sbls_control;
};

detailed documentation#

control derived type as a C struct

components#

bool f_indexing

use C or Fortran sparse matrix indexing

ipc_ error

error and warning diagnostics occur on stream error

ipc_ out

general output occurs on stream out

ipc_ print_level

the level of output required is specified by print_level

ipc_ start_print

any printing will start on this iteration

ipc_ stop_print

any printing will stop on this iteration

ipc_ maxit

at most maxit inner iterations are allowed

ipc_ factor

the factorization to be used. Possible values are

  • 0 automatic

  • 1 Schur-complement factorization

  • 2 augmented-system factorization

ipc_ max_col

the maximum number of nonzeros in a column of A which is permitted with the Schur-complement factorization

ipc_ indmin

an initial guess as to the integer workspace required by SBLS

ipc_ valmin

an initial guess as to the real workspace required by SBLS

ipc_ itref_max

the maximum number of iterative refinements allowed

ipc_ infeas_max

the number of iterations for which the overall infeasibility of the problem is not reduced by at least a factor .reduce_infeas before the problem is flagged as infeasible (see reduce_infeas)

ipc_ muzero_fixed

the initial value of the barrier parameter will not be changed for the first muzero_fixed iterations

ipc_ restore_problem

indicate whether and how much of the input problem should be restored on output. Possible values are

  • 0 nothing restored

  • 1 scalar and vector parameters

  • 2 all parameters

ipc_ indicator_type

specifies the type of indicator function used. Possible values are

  • 1 primal indicator: constraint active if and only if the distance to nearest bound \(\leq\).indicator_p_tol

  • 2 primal-dual indicator: constraint active if and only if the distance to nearest bound \(\leq\).indicator_tol_pd \* size of corresponding multiplier

  • 3 primal-dual indicator: constraint active if and only if the distance to the nearest bound \(\leq\).indicator_tol_tapia \* distance to same bound at previous iteration

ipc_ extrapolate

should extrapolation be used to track the central path? Possible values

  • 0 never

  • 1 after the final major iteration

  • 2 at each major iteration (unused at present)

ipc_ path_history

the maximum number of previous path points to use when fitting the data (unused at present)

ipc_ path_derivatives

the maximum order of path derivative to use (unused at present)

ipc_ fit_order

the order of (Puiseux) series to fit to the path data: $

\[\]

to fit all data (unused at present)

ipc_ sif_file_device

specifies the unit number to write generated SIF file describing the current problem

rpc_ infinity

any bound larger than infinity in modulus will be regarded as infinite

rpc_ stop_p

the required accuracy for the primal infeasibility

rpc_ stop_d

the required accuracy for the dual infeasibility

rpc_ stop_c

the required accuracy for the complementarity

rpc_ prfeas

initial primal variables will not be closer than prfeas from their bounds

rpc_ dufeas

initial dual variables will not be closer than dufeas from their bounds

rpc_ muzero

the initial value of the barrier parameter. If muzero is not positive, it will be reset to an appropriate value

rpc_ reduce_infeas

if the overall infeasibility of the problem is not reduced by at least a factor reduce_infeas over .infeas_max iterations, the problem is flagged as infeasible (see infeas_max)

rpc_ potential_unbounded

if W=0 and the potential function value is smaller than potential_unbounded * number of one-sided bounds, the analytic center will be flagged as unbounded

rpc_ pivot_tol

the threshold pivot used by the matrix factorization. See the documentation for SBLS for details

rpc_ pivot_tol_for_dependencies

the threshold pivot used by the matrix factorization when attempting to detect linearly dependent constraints. See the documentation for SBLS for details

rpc_ zero_pivot

any pivots smaller than zero_pivot in absolute value will be regarded to zero when attempting to detect linearly dependent constraints

rpc_ identical_bounds_tol

any pair of constraint bounds (c_l,c_u) or (x_l,x_u) that are closer tha identical_bounds_tol will be reset to the average of their values

rpc_ mu_min

start terminal extrapolation when mu reaches mu_min

rpc_ indicator_tol_p

if .indicator_type = 1, a constraint/bound will be deemed to be active if and only if the distance to nearest bound $ \(\leq\).indicator_p_tol

rpc_ indicator_tol_pd

if .indicator_type = 2, a constraint/bound will be deemed to be active if and only if the distance to nearest bound $ \(\leq\).indicator_tol_pd \* size of corresponding multiplier

rpc_ indicator_tol_tapia

if .indicator_type = 3, a constraint/bound will be deemed to be active if and only if the distance to nearest bound $ \(\leq\).indicator_tol_tapia \* distance to same bound at previous iteration

rpc_ cpu_time_limit

the maximum CPU time allowed (-ve means infinite)

rpc_ clock_time_limit

the maximum elapsed clock time allowed (-ve means infinite)

bool remove_dependencies

the equality constraints will be preprocessed to remove any linear dependencies if true

bool treat_zero_bounds_as_general

any problem bound with the value zero will be treated as if it were a general value if true

bool just_feasible

if .just_feasible is true, the algorithm will stop as soon as a feasible point is found. Otherwise, the optimal solution to the problem will be found

bool getdua

if .getdua, is true, advanced initial values are obtained for the dual variables

bool puiseux

If extrapolation is to be used, decide between Puiseux and Taylor series.

bool feasol

if .feasol is true, the final solution obtained will be perturbed so tha variables close to their bounds are moved onto these bounds

bool balance_initial_complentarity

if .balance_initial_complentarity is true, the initial complemetarity is required to be balanced

bool use_corrector

if .use_corrector, a corrector step will be used

bool array_syntax_worse_than_do_loop

if .array_syntax_worse_than_do_loop is true, f77-style do loops will be used rather than f90-style array syntax for vector operations

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 generate_sif_file

if .generate_sif_file is .true. if a SIF file describing the current problem is to be generated

char sif_file_name[31]

name of generated SIF file containing input problem

char prefix[31]

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’

struct fdc_control_type fdc_control

control parameters for FDC

struct sbls_control_type sbls_control

control parameters for SBLS