util.c File Reference

This file contains all the utility routines. More...

#include <slim.h>

Go to the source code of this file.

Functions
ctrl_t *	create_ctrl ()
	Create a ctrl structure wich contains all the default parameters for SLIM.
void	free_ctrl (ctrl_t *ctrl)
	Free a ctrl structure.
void	start_timer (ctimer_t *ctimer)
	Start a timer to record current time.
void	end_timer (ctimer_t *ctimer)
	End a timer to record a length of a duration.
void	display_timer (ctimer_t *ctimer, char *msg)
	Display a user-defined message and a duration length recorded by a timer.
int	count_nnz (double *array, int narray)
	Count the number of non-zero values in an array.
void	find_topk (double *w, int n, int topk, double *map, int *topk2)
	Find the top-k values from an array.
void	get_column (gk_csr_t *constraint, int i, double *w)
	Get a column from a csr matrix.

Detailed Description

This file contains all the utility routines.

Definition in file util.c.

Function Documentation

int count_nnz	(	double *	array,
		int	narray
	)

Count the number of non-zero values in an array.

Parameters

[in]	array	An array whose non-zero values will be counted
[in]	narray	The length of the array

Returns

int The number of non-zero values in the array

Definition at line 134 of file util.c.

References EPSILON2.

Referenced by slim_fs_learn().

                                         {

  int nnz = 0; 

  for (int i = 0; i < narray; i ++){
    if (array[i] > EPSILON2 || array[i] < -EPSILON2)
      nnz ++; 
  }

  return nnz; 

}

ctrl_t* create_ctrl

(

)

Create a ctrl structure wich contains all the default parameters for SLIM.

Returns

ctrl_t* A pointer to a created ctrl structure

Definition at line 21 of file util.c.

References ctrl_t::beta, ctrl_t::bl, ctrl_t::bsize, ctrl_t::bu, ctrl_t::dbglvl, ctrl_t::endi, ctrl_t::fs, ctrl_t::fs_file, ctrl_t::k, ctrl_t::lambda, ctrl_t::max_bcls_niters, ctrl_t::model_file, ctrl_t::nratings, ctrl_t::optTol, ctrl_t::pred_file, ctrl_t::starti, ctrl_t::test_file, ctrl_t::topn, ctrl_t::train_file, and ctrl_t::transpose.

Referenced by main(), and parse_cmdline().

                      {

  ctrl_t * ctrl = gk_malloc(sizeof(ctrl_t), "malloc ctrl"); 

  ctrl->train_file = NULL; 
  ctrl->test_file  = NULL; 
  ctrl->model_file = NULL; 
  ctrl->fs_file = NULL;
  ctrl->pred_file = NULL; 

  ctrl->dbglvl = 0; 

  ctrl->beta    = 1.0; 
  ctrl->lambda  = 1.0; 

  ctrl->starti = -1; 
  ctrl->endi = -1; 

  ctrl->optTol = 1e-5; 
  ctrl->max_bcls_niters = 100000; 

  ctrl->bl = 0;     
  ctrl->bu = 1e20;  

  ctrl->fs = 0;

  ctrl->k = 50;

  ctrl->bsize = 1000; 

  ctrl->nratings = 5; 

  ctrl->topn = 10; 

  ctrl->transpose = 0; 

  return ctrl; 

}

void display_timer	(	ctimer_t *	ctimer,
		char *	msg
	)

Display a user-defined message and a duration length recorded by a timer.

Parameters

[in]	ctimer	A timer with a length of a duration recorded
[in]	msg	A user-defined message to display

Definition at line 116 of file util.c.

References ctimer_t::end, and ctimer_t::start.

Referenced by slim_learn(), and slim_test().

                                                 {

  printf("----- elapsed CPU time for %s: %f s\n", msg, 
         (double)(ctimer->end - ctimer->start)/CLOCKS_PER_SEC);  
  fflush(stdout);

}

void end_timer

(

ctimer_t *

ctimer

)

End a timer to record a length of a duration.

Parameters

[in]

ctimer

A timer to end

Definition at line 101 of file util.c.

References ctimer_t::end.

Referenced by slim_learn(), and slim_test().

                                 {

  ctimer->end = clock(); 
  
}

void find_topk	(	double *	w,
		int	n,
		int	topk,
		double *	map,
		int *	topk2
	)

Find the top-k values from an array.

Parameters

[in]	w	The array whose top-k values will be found
[in]	n	The length of the array w
[in]	topk	The number of top values to be found
[out]	map	The array of indices that correspond to the top-k values in the input array
[out]	topk2	The actual number of top values that are found

Definition at line 159 of file util.c.

Referenced by slim_fs_learn().

                                                                      {


  gk_dkv_t * wkv = gk_malloc(sizeof(gk_dkv_t)*n, "malloc wkv"); 
  int k2 = 0; 

  for (int i = 0; i < n; i ++){
    wkv[i].key = w[i]; 
    wkv[i].val = i; 
    if (w[i] > 1e-10) k2 ++; 
  }

  /* sort */
  gk_dkvsortd(n, wkv); 

  for (int i = 0; i < ((topk <= k2)? topk:k2); i ++){
    map[i] = wkv[i].val; 
  }
  
  *topk2 = ((topk <= k2)? topk:k2);
  gk_free((void **)&wkv, LTERM); 

}

void free_ctrl

(

ctrl_t *

ctrl

)

Free a ctrl structure.

Parameters

[in]

ctrl

A pointer to a ctrl structure to be freed

Definition at line 68 of file util.c.

References ctrl_t::fs_file, ctrl_t::model_file, ctrl_t::pred_file, ctrl_t::test_file, and ctrl_t::train_file.

Referenced by main().

                             {

  gk_free((void **)&ctrl->model_file, LTERM); 
  gk_free((void **)&ctrl->train_file, LTERM); 
  gk_free((void **)&ctrl->test_file, LTERM); 
  gk_free((void **)&ctrl->pred_file, LTERM); 
  gk_free((void **)&ctrl->fs_file, LTERM); 

  gk_free((void **)&ctrl, LTERM); 

}

void get_column	(	gk_csr_t *	constraint,
		int	i,
		double *	w
	)

Get a column from a csr matrix.

Parameters

[in]	constraint	A matrix from which one column is to be retrievd
[in]	i	The index of the column to be retrieved
[out]	w	The output vector which saves the retrieved column

Definition at line 194 of file util.c.

Referenced by slim_learn().

                                                         {
 
  if (i > constraint->ncols){
    gk_dset(constraint->nrows, 0, w); 
  }
  else{
    int nnz = constraint->colptr[i+1] - constraint->colptr[i]; 
    for (int j = 0; j < nnz; j ++){
      int k = *(constraint->colptr[i] + j + constraint->colind); 
      w[k]  = *(constraint->colptr[i] + j + constraint->colval); 
    }
  }
}

void start_timer

(

ctimer_t *

ctimer

)

Start a timer to record current time.

Parameters

[in]

ctimer

A timer to start

Definition at line 88 of file util.c.

References ctimer_t::start.

Referenced by slim_learn(), and slim_test().

                                   {
  
  ctimer->start = clock(); 
  
}