callable functions#

    function uls_initialize(solver, data, control, status)

Set default control values and initialize private data

Select solver, set default control values and initialize private data

Parameters:

solver	is a one-dimensional array of type Vararg{Cchar} that specifies the solver package that should be used to factorize the matrix $A$. It should be one of ‘gls’, ‘ma28’, ‘ma48 or ‘getr’; lower or upper case variants are allowed.
data	holds private internal data
control	is a structure containing control information (see uls_control_type)
status	is a scalar variable of type Int32 that gives the exit status from the package. Possible values are: 0 The initialization was successful. -26 The requested solver is not available.

    function uls_read_specfile(control, specfile)

Read the content of a specification file, and assign values associated with given keywords to the corresponding control parameters. An in-depth discussion of specification files is available, and a detailed list of keywords with associated default values is provided in $GALAHAD/src/uls/ULS.template. See also Table 2.1 in the Fortran documentation provided in $GALAHAD/doc/uls.pdf for a list of how these keywords relate to the components of the control structure.

Parameters:

control	is a structure containing control information (see uls_control_type)
specfile	is a one-dimensional array of type Vararg{Cchar} that must give the name of the specification file

    function uls_factorize_matrix(control, data, status,
                                  m, n, type, ne, val, row, col, ptr)

Import matrix data into internal storage prior to solution, analyse the sparsity patern, and subsequently factorize the matrix

Parameters:

control	is a structure whose members provide control parameters for the remaining procedures (see uls_control_type)
data	holds private internal data
status	is a scalar variable of type Int32 that gives the exit status from the package. Possible values are: 0 The import, analysis and factorization were conducted successfully. -1 An allocation error occurred. A message indicating the offending array is written on unit control.error, and the returned allocation status and a string containing the name of the offending array are held in inform.alloc_status and inform.bad_alloc respectively. -2 A deallocation error occurred. A message indicating the offending array is written on unit control.error and the returned allocation status and a string containing the name of the offending array are held in inform.alloc_status and inform.bad_alloc respectively. -3 The restrictions n > 0 and m> 0 or requirement that the matrix type must contain the relevant string ‘dense’, ‘coordinate’ or ‘sparse_by_rows has been violated. -26 The requested solver is not available. -29 This option is not available with this solver. -32 More than control.max integer factor size words of internal integer storage are required for in-core factorization. -50 A solver-specific error occurred; check the solver-specific information component of inform along with the solver’s documentation for more details.
m	is a scalar variable of type Int32 that holds the number of rows in the unsymmetric matrix $A$.
n	is a scalar variable of type Int32 that holds the number of columns in the unsymmetric matrix $A$.
type	is a one-dimensional array of type Vararg{Cchar} that specifies the unsymmetric storage scheme used for the matrix $A$. It should be one of ‘coordinate’, ‘sparse_by_rows’ or ‘dense’; lower or upper case variants are allowed.
ne	is a scalar variable of type Int32 that holds the number of entries in $A$ in the sparse co-ordinate storage scheme. It need not be set for any of the other schemes.
val	is a one-dimensional array of size ne and type T, that holds the values of the entries of the matrix $A$ in any of the supported storage schemes.
row	is a one-dimensional array of size ne and type Int32 that holds the row indices of the matrix $A$ in the sparse co-ordinate storage scheme. It need not be set for any of the other three schemes, and in this case can be C_NULL.
col	is a one-dimensional array of size ne and type Int32 that holds the column indices of the matrix $A$ in either the sparse co-ordinate, or the sparse row-wise storage scheme. It need not be set when the dense storage schemes is used, and in this case can be C_NULL.
ptr	is a one-dimensional array of size m+1 and type Int32 that holds the starting position of each row of the matrix $A$, as well as the total number of entries, in the sparse row-wise storage scheme. It need not be set when the other schemes are used, and in this case can be C_NULL.

    function uls_reset_control(control, data, status)

Reset control parameters after import if required.

Parameters:

control

is a structure whose members provide control parameters for the remaining procedures (see uls_control_type)

data

holds private internal data

status

is a scalar variable of type Int32 that gives the exit status from the package. Possible values are:

0
The import was successful.

    function uls_solve_system(data, status, m, n, sol, trans)

Solve the linear system $Ax=b$ or $A^Tx=b$.

Parameters:

data	holds private internal data
status	is a scalar variable of type Int32 that gives the exit status from the package. Possible values are: 0 The required solution was obtained. -1 An allocation error occurred. A message indicating the offending array is written on unit control.error, and the returned allocation status and a string containing the name of the offending array are held in inform.alloc_status and inform.bad_alloc respectively. -2 A deallocation error occurred. A message indicating the offending array is written on unit control.error and the returned allocation status and a string containing the name of the offending array are held in inform.alloc_status and inform.bad_alloc respectively. -34 The package PARDISO failed; check the solver-specific information components inform.pardiso iparm and inform.pardiso_dparm along with PARDISO’s documentation for more details. -35 The package WSMP failed; check the solver-specific information components inform.wsmp_iparm and inform.wsmp dparm along with WSMP’s documentation for more details.
m	is a scalar variable of type Int32 that holds the number of rows in the unsymmetric matrix $A$.
n	is a scalar variable of type Int32 that holds the number of columns in the unsymmetric matrix $A$.
sol	is a one-dimensional array of size n and type T. On entry, it must hold the vector $b$. On a successful exit, its contains the solution $x$.
trans	is a scalar variable of type Bool, that specifies whether to solve the equation $A^Tx=b$ (trans=true) or $Ax=b$ (trans=false).

    function uls_information(data, inform, status)

Provides output information

Parameters:

data

holds private internal data

inform

is a structure containing output information (see uls_inform_type)

status

is a scalar variable of type Int32 that gives the exit status from the package. Possible values are (currently):

0
The values were recorded successfully

    function uls_terminate(data, control, inform)

Deallocate all internal private storage

Parameters:

data	holds private internal data
control	is a structure containing control information (see uls_control_type)
inform	is a structure containing output information (see uls_inform_type)