overview of functions provided#

// typedefs

typedef float spc_;
typedef double rpc_;
typedef int ipc_;

// structs

struct sls_control_type;
struct sls_inform_type;
struct sls_time_type;

// global functions

void sls_initialize(
    const char solver[],
    void **data,
    struct sls_control_type* control,
    ipc_ *status
);

void sls_read_specfile(struct sls_control_type* control, const char specfile[]);

void sls_analyse_matrix(
    struct sls_control_type* control,
    void **data,
    ipc_ *status,
    ipc_ n,
    const char type[],
    ipc_ ne,
    const ipc_ row[],
    const ipc_ col[],
    const ipc_ ptr[]
);

void sls_reset_control(
    struct sls_control_type* control,
    void **data,
    ipc_ *status
);

void sls_factorize_matrix(
    void **data,
    ipc_ *status,
    ipc_ ne,
    const rpc_ val[]
);

void sls_solve_system(void **data, ipc_ *status, ipc_ n, rpc_ sol[]);

void sls_partial_solve_system(
    const char part[],
    void **data,
    ipc_ *status,
    ipc_ n,
    rpc_ sol[]
);

void sls_information(void **data, struct sls_inform_type* inform, ipc_ *status);

void sls_terminate(
    void **data,
    struct sls_control_type* control,
    struct sls_inform_type* inform
);

typedefs#

typedef float spc_

spc_ is real single precision

typedef double rpc_

rpc_ is the real working precision used, but may be changed to float by defining the preprocessor variable REAL_32 or (if supported) to __real128 using the variable REAL_128.

typedef int ipc_

ipc_ is the default integer word length used, but may be changed to int64_t by defining the preprocessor variable INTEGER_64.

function calls#

void sls_initialize(
    const char solver[],
    void **data,
    struct sls_control_type* control,
    ipc_ *status
)

Select solver, set default control values and initialize private data

Parameters:

solver	is a one-dimensional array of type char that specifies the solver package that should be used to factorize the matrix $A$. It should be one of ‘sils’, ‘ma27’, ‘ma57’, ‘ma77’, ‘ma86’, ‘ma87’, ‘ma97’, ‘ssids’, ‘mumps’, ‘pardiso’, ‘mkl pardiso’, ‘pastix’, ‘wsmp’, ‘potr’, ‘sytr’ or ‘pbtr’; lower or upper case variants are allowed. Only ‘potr’, ‘sytr’, ‘pbtr’ and, for OMP 4.0-compliant compilers, ‘ssids’ are installed by default, but others are easily installed (see README.external).
data	holds private internal data
control	is a struct containing control information (see sls_control_type)
status	is a scalar variable of type ipc_, that gives the exit status from the package. Possible values are: 0 The initialization was successful. -26 The requested solver is not available.

void sls_read_specfile(struct sls_control_type* control, const char 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/sls/SLS.template. See also Table 2.1 in the Fortran documentation provided in $GALAHAD/doc/sls.pdf for a list of how these keywords relate to the components of the control structure.

Parameters:

control	is a struct containing control information (see sls_control_type)
specfile	is a character string containing the name of the specification file

void sls_analyse_matrix(
    struct sls_control_type* control,
    void **data,
    ipc_ *status,
    ipc_ n,
    const char type[],
    ipc_ ne,
    const ipc_ row[],
    const ipc_ col[],
    const ipc_ ptr[]
)

Import structural matrix data into internal storage prior to solution

Parameters:

control	is a struct whose members provide control paramters for the remaining prcedures (see sls_control_type)
data	holds private internal data
status	is a scalar variable of type ipc_, that gives the exit status from the package. Possible values are: 0 The import and analysis 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 or requirement that the matrix type must contain the relevant string ‘dense’, ‘coordinate’ or ‘sparse_by_rows has been violated. -20 The matrix is not positive definite while the solver used expected it to be. -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. -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. -36 The scaling package HSL MC64 failed; check the solver-specific information component inform.mc64_info along with HSL MC64’s documentation for more details. -37 The scaling package MC77 failed; check the solver-specific information components inform.mc77 info and inform.mc77_rinfo along with MC77’s documentation for more details. -43 A direct-access file error occurred. See the value of inform.ma77_info.flag for more details. -50 A solver-specific error occurred; check the solver-specific information component of inform along with the solver’s documentation for more details.
n	is a scalar variable of type ipc_, that holds the number of rows in the symmetric matrix $A$.
type	is a one-dimensional array of type char that specifies the symmetric 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 ipc_, that holds the number of entries in the lower triangular part of $A$ in the sparse co-ordinate storage scheme. It need not be set for any of the other schemes.
row	is a one-dimensional array of size ne and type ipc_, that holds the row indices of the lower triangular part of $A$ 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 NULL.
col	is a one-dimensional array of size ne and type ipc_, that holds the column indices of the lower triangular part of $A$ in either the sparse co-ordinate, or the sparse row-wise storage scheme. It need not be set when the dense storage scheme is used, and in this case can be NULL.
ptr	is a one-dimensional array of size n+1 and type ipc_, that holds the starting position of each row of the lower triangular part of $A$, 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 NULL.

void sls_reset_control(
    struct sls_control_type* control,
    void **data,
    ipc_ *status
)

Reset control parameters after import if required.

Parameters:

control

is a struct whose members provide control paramters for the remaining prcedures (see sls_control_type)

data

holds private internal data

status

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

1. The import was successful.

void sls_factorize_matrix(
    void **data,
    ipc_ *status,
    ipc_ ne,
    const rpc_ val[]
)

Form and factorize the symmetric matrix $A$.

Parameters:

data	holds private internal data
status	is a scalar variable of type ipc_, that gives the exit status from the package. Possible values are: 0 The factors were generated 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 or requirement that the matrix type must contain the relevant string ‘dense’, ‘coordinate’ or ‘sparse_by_rows has been violated. -20 The matrix is not positive definite while the solver used expected it to be. -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. -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. -36 The scaling package HSL MC64 failed; check the solver-specific information component inform.mc64_info along with HSL MC64’s documentation for more details. -37 The scaling package MC77 failed; check the solver-specific information components inform.mc77 info and inform.mc77_rinfo along with MC77’s documentation for more details. -43 A direct-access file error occurred. See the value of inform.ma77_info.flag for more details. -50 A solver-specific error occurred; check the solver-specific information component of inform along with the solver’s documentation for more details.
ne	is a scalar variable of type ipc_, that holds the number of entries in the lower triangular part of the symmetric matrix $A$.
val	is a one-dimensional array of size ne and type rpc_, that holds the values of the entries of the lower triangular part of the symmetric matrix $A$ in any of the supported storage schemes.

void sls_solve_system(void **data, ipc_ *status, ipc_ n, rpc_ sol[])

Solve the linear system $Ax=b$.

Parameters:

data	holds private internal data
status	is a scalar variable of type ipc_, 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.
n	is a scalar variable of type ipc_, that holds the number of entries in the vectors $b$ and $x$.
sol	is a one-dimensional array of size n and type double. On entry, it must hold the vector $b$. On a successful exit, its contains the solution $x$.

void sls_partial_solve_system(
    const char part[],
    void **data,
    ipc_ *status,
    ipc_ n,
    rpc_ sol[]
)

Given the factorization $A = L D U$ with $U = L^T$, solve the linear system $Mx=b$, where $M$ is one of $L$, $D$, $U$ or $S = L \sqrt{D}$.

Parameters:

part	is a one-dimensional array of type char that specifies the component $M$ of the factorization that is to be used. It should be one of “L”, “D”, “U” or “S”, and these correspond to the parts $L$, $D$, $U$ and $S$; lower or upper case variants are allowed.
data	holds private internal data
status	is a scalar variable of type ipc_, that gives the entry and exit status from the package. On initial entry, status must be set to 1. Possible exit 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.
n	is a scalar variable of type ipc_, that holds the number of entries in the vectors $b$ and $x$.
sol	is a one-dimensional array of size n and type double. On entry, it must hold the vector $b$. On a successful exit, its contains the solution $x$.

void sls_information(void **data, struct sls_inform_type* inform, ipc_ *status)

Provide output information

Parameters:

data

holds private internal data

inform

is a struct containing output information (see sls_inform_type)

status

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

0
The values were recorded successfully

void sls_terminate(
    void **data,
    struct sls_control_type* control,
    struct sls_inform_type* inform
)

Deallocate all internal private storage

Parameters:

data	holds private internal data
control	is a struct containing control information (see sls_control_type)
inform	is a struct containing output information (see sls_inform_type)