/* ========================================================================== */
/* === symamdtest mexFunction =============================================== */
/* ========================================================================== */

/* SYMAMD test function

    This MATLAB mexFunction is for testing only.  It is not meant for
    production use.  See symamdmex.c instead.

    Usage:

	[ P, stats ] = symamdtest (A, knobs) ;

    See symamd.m for a description.  knobs is required.

	knobs (1)	dense row control
	knobs (2)	spumoni
	knobs (3)	for testing only.  Controls how the input matrix is
			jumbled prior to calling symamd, to test its error
			handling capability.

    Authors:

	The authors of the code itself are Stefan I. Larimore and Timothy A.
	Davis (DrTimothyAldenDavis@gmail.com).  The algorithm was
	developed in collaboration with John Gilbert, Xerox PARC, and Esmond
	Ng, Oak Ridge National Laboratory.

    Acknowledgements:

	This work was supported by the National Science Foundation, under
	grants DMS-9504974 and DMS-9803599.

    Notice:

	Copyright (c) 1998-2007, Timothy A. Davis.  All Rights Reserved.
	See COLAMD/Doc/License.txt for the License.

    Availability:

	The colamd/symamd library is available at http://www.suitesparse.com

*/

/* ========================================================================== */
/* === Include files ======================================================== */
/* ========================================================================== */

#include "colamd.h"
#include "mex.h"
#include "matrix.h"
#include <stdlib.h>
#include <string.h>
#define Long SuiteSparse_long

static void dump_matrix
(
    Long A [ ],
    Long p [ ],
    Long n_row,
    Long n_col,
    Long Alen,
    Long limit
) ;

/* ========================================================================== */
/* === symamd mexFunction =================================================== */
/* ========================================================================== */

void mexFunction
(
    /* === Parameters ======================================================= */

    int nlhs,			/* number of left-hand sides */
    mxArray *plhs [],		/* left-hand side matrices */
    int nrhs,			/* number of right--hand sides */
    const mxArray *prhs []	/* right-hand side matrices */
)
{
    /* === Local variables ================================================== */

    Long *perm ;                /* column ordering of M and ordering of A */
    Long *A ;                   /* row indices of input matrix A */
    Long *p ;                   /* column pointers of input matrix A */
    Long n_col ;                /* number of columns of A */
    Long n_row ;                /* number of rows of A */
    Long full ;                 /* TRUE if input matrix full, FALSE if sparse */
    double knobs [COLAMD_KNOBS] ; /* colamd user-controllable parameters */
    double *out_perm ;          /* output permutation vector */
    double *out_stats ;         /* output stats vector */
    double *in_knobs ;          /* input knobs vector */
    Long i ;                    /* loop counter */
    mxArray *Ainput ;           /* input matrix handle */
    Long spumoni ;              /* verbosity variable */
    Long stats2 [COLAMD_STATS] ;/* stats for symamd */

    Long *cp, *cp_end, result, nnz, col, length ;
    Long *stats ;
    stats = stats2 ;

    /* === Check inputs ===================================================== */

    if (nrhs < 1 || nrhs > 2 || nlhs < 0 || nlhs > 2)
    {
	mexErrMsgTxt (
	"symamd: incorrect number of input and/or output arguments.") ;
    }

    if (nrhs != 2)
    {
	mexErrMsgTxt ("symamdtest: knobs are required") ;
    }
    /* for testing we require all 3 knobs */
    if (mxGetNumberOfElements (prhs [1]) != 3)
    {
	mexErrMsgTxt ("symamdtest: must have all 3 knobs for testing") ;
    }

    /* === Get knobs ======================================================== */

    colamd_l_set_defaults (knobs) ;
    spumoni = 0 ;

    /* check for user-passed knobs */
    if (nrhs == 2)
    {
	in_knobs = mxGetPr (prhs [1]) ;
	i = mxGetNumberOfElements (prhs [1]) ;
	if (i > 0) knobs [COLAMD_DENSE_ROW] = in_knobs [0] ;
	if (i > 1) spumoni = (Long) in_knobs [1] ;
    }

    /* print knob settings if spumoni is set */
    if (spumoni)
    {
	mexPrintf ("\nsymamd version %d.%d, %s:\n",
	    COLAMD_MAIN_VERSION, COLAMD_SUB_VERSION, COLAMD_DATE) ;
	if (knobs [COLAMD_DENSE_ROW] >= 0)
	{
	    mexPrintf ("knobs(1): %g, rows/cols with > "
		"max(16,%g*sqrt(size(A,2))) entries removed\n",
		in_knobs [0], knobs [COLAMD_DENSE_ROW]) ;
	}
	else
	{
	    mexPrintf ("knobs(1): %g, no dense rows removed\n", in_knobs [0]) ;
	}
	mexPrintf ("knobs(2): %g, statistics and knobs printed\n",
	    in_knobs [1]) ;
	mexPrintf ("Testing %d\n", in_knobs [2]) ;
    }

    /* === If A is full, convert to a sparse matrix ========================= */

    Ainput = (mxArray *) prhs [0] ;
    if (mxGetNumberOfDimensions (Ainput) != 2)
    {
	mexErrMsgTxt ("symamd: input matrix must be 2-dimensional.") ;
    }
    full = !mxIsSparse (Ainput) ;
    if (full)
    {
	mexCallMATLAB (1, &Ainput, 1, (mxArray **) prhs, "sparse") ;
    }

    /* === Allocate workspace for symamd ==================================== */

    /* get size of matrix */
    n_row = mxGetM (Ainput) ;
    n_col = mxGetN (Ainput) ;
    if (n_col != n_row)
    {
	mexErrMsgTxt ("symamd: matrix must be square.") ;
    }

    /* p = mxGetJc (Ainput) ; */
    p = (Long *) mxCalloc (n_col+1, sizeof (Long)) ;
    (void) memcpy (p, mxGetJc (Ainput), (n_col+1)*sizeof (Long)) ;

    nnz = p [n_col] ;
    if (spumoni > 0)
    {
	mexPrintf ("symamdtest: nnz %d\n", nnz) ;
    }

    /* A = mxGetIr (Ainput) ; */
    A = (Long *) mxCalloc (nnz+1, sizeof (Long)) ;
    (void) memcpy (A, mxGetIr (Ainput), nnz*sizeof (Long)) ;

    perm = (Long *) mxCalloc (n_col+1, sizeof (Long)) ;

/* === Jumble matrix ======================================================== */


/*
	knobs [2]	FOR TESTING ONLY: Specifies how to jumble matrix
			0 : No jumbling
			1 : (no errors)
			2 : Make first pointer non-zero
			3 : Make column pointers not non-decreasing
			4 : (no errors)
			5 : Make row indices not strictly increasing
			6 : Make a row index greater or equal to n_row
			7 : Set A = NULL
			8 : Set p = NULL
			9 : Repeat row index
			10: make row indices not sorted
			11: jumble columns massively (note this changes
				the pattern of the matrix A.)
			12: Set stats = NULL
			13: Make n_col less than zero
*/

    /* jumble appropriately */
    switch ((Long) in_knobs [2])
    {

	case 0 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: no errors expected\n") ;
	    }
	    result = 1 ;		/* no errors */
	    break ;

	case 1 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: no errors expected (1)\n") ;
	    }
	    result = 1 ;
	    break ;

	case 2 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: p [0] nonzero\n") ;
	    }
	    result = 0 ;		/* p [0] must be zero */
	    p [0] = 1 ;
	    break ;

	case 3 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: negative length last column\n") ;
	    }
	    result = (n_col == 0) ;	/* p must be monotonically inc. */
	    p [n_col] = p [0] ;
	    break ;

	case 4 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: no errors expected (4)\n") ;
	    }
	    result = 1 ;
	    break ;

	case 5 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: row index out of range (-1)\n") ;
	    }
	    if (nnz > 0)		/* row index out of range */
	    {
		result = 0 ;
		A [nnz-1] = -1 ;
	    }
	    else
	    {
	        if (spumoni > 0)
		{
		    mexPrintf ("Note: no row indices to put out of range\n") ;
		}
		result = 1 ;
	    }
	    break ;

	case 6 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: row index out of range (ncol)\n") ;
	    }
	    if (nnz > 0)		/* row index out of range */
	    {
		result = 0 ;
		A [nnz-1] = n_col ;
	    }
	    else
	    {
	        if (spumoni > 0)
		{
		    mexPrintf ("Note: no row indices to put out of range\n") ;
		}
		result = 1 ;
	    }
	    break ;

	case 7 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: A not present\n") ;
	    }
	    result = 0 ;		/* A not present */
	    A = (Long *) NULL ;
	    break ;

	case 8 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: p not present\n") ;
	    }
	    result = 0 ;		/* p not present */
	    p = (Long *) NULL ;
	    break ;

	case 9 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: duplicate row index\n") ;
	    }
	    result = 1 ;		/* duplicate row index */

	    for (col = 0 ; col < n_col ; col++)
	    {
		length = p [col+1] - p [col] ;
	    	if (length > 1)
		{
		    A [p [col+1]-2] = A [p [col+1] - 1] ;
		    if (spumoni > 0)
		    {
			mexPrintf ("Made duplicate row %d in col %d\n",
		    	 A [p [col+1] - 1], col) ;
		    }
		    break ;
		}
	    }

	    if (spumoni > 1)
	    {
		dump_matrix (A, p, n_row, n_col, nnz, col+2) ;
	    }
	    break ;

	case 10 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: unsorted column\n") ;
	    }
	    result = 1 ;		/* jumbled columns */

	    for (col = 0 ; col < n_col ; col++)
	    {
		length = p [col+1] - p [col] ;
	    	if (length > 1)
		{
		    i = A[p [col]] ;
		    A [p [col]] = A[p [col] + 1] ;
		    A [p [col] + 1] = i ;
		    if (spumoni > 0)
		    {
			mexPrintf ("Unsorted column %d \n", col) ;
		    }
		    break ;
		}
	    }

	    if (spumoni > 1)
	    {
		dump_matrix (A, p, n_row, n_col, nnz, col+2) ;
	    }
	    break ;

	case 11 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: massive jumbling\n") ;
	    }
	    result = 1 ;		/* massive jumbling, but no errors */
	    srand (1) ;
	    for (i = 0 ; i < n_col ; i++)
	    {
		cp = &A [p [i]] ;
		cp_end = &A [p [i+1]] ;
		while (cp < cp_end)
		{
		    *cp++ = rand() % n_row ;
		}
	    }
	    if (spumoni > 1)
	    {
		dump_matrix (A, p, n_row, n_col, nnz, n_col) ;
	    }
	    break ;

	case 12 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: stats not present\n") ;
	    }
	    result = 0 ;		/* stats not present */
	    stats = (Long *) NULL ;
	    break ;

	case 13 :
	    if (spumoni > 0)
	    {
		mexPrintf ("symamdtest: ncol out of range\n") ;
	    }
	    result = 0 ;		/* ncol out of range */
	    n_col = -1 ;
	    break ;

    }

    /* === Order the rows and columns of A (does not destroy A) ============= */

    if (!symamd_l (n_col, A, p, perm, knobs, stats, &mxCalloc, &mxFree))
    {

	/* return p = -1 if colamd failed */
	plhs [0] = mxCreateDoubleMatrix (1, 1, mxREAL) ;
	out_perm = mxGetPr (plhs [0]) ;
	out_perm [0] = -1 ;
	mxFree (p) ;
	mxFree (A) ;

	if (spumoni > 0 || result)
	{
	    symamd_l_report (stats) ;
	}

	if (result)
	{
	    mexErrMsgTxt ("symamd should have returned TRUE\n") ;
	}

	return ;
	/* mexErrMsgTxt ("symamd error!") ; */
    }

    if (!result)
    {
	symamd_l_report (stats) ;
	mexErrMsgTxt ("symamd should have returned FALSE\n") ;
    }

    if (full)
    {
	mxDestroyArray (Ainput) ;
    }

    /* === Return the permutation vector ==================================== */

    plhs [0] = mxCreateDoubleMatrix (1, n_col, mxREAL) ;
    out_perm = mxGetPr (plhs [0]) ;
    for (i = 0 ; i < n_col ; i++)
    {
	/* symamd is 0-based, but MATLAB expects this to be 1-based */
	out_perm [i] = perm [i] + 1 ;
    }
    mxFree (perm) ;

    /* === Return the stats vector ========================================== */

    /* print stats if spumoni > 0 */
    if (spumoni > 0)
    {
	symamd_l_report (stats) ;
    }

    if (nlhs == 2)
    {
	plhs [1] = mxCreateDoubleMatrix (1, COLAMD_STATS, mxREAL) ;
	out_stats = mxGetPr (plhs [1]) ;
	for (i = 0 ; i < COLAMD_STATS ; i++)
	{
	    out_stats [i] = stats [i] ;
	}

	/* fix stats (5) and (6), for 1-based information on jumbled matrix. */
	/* note that this correction doesn't occur if symamd returns FALSE */
	out_stats [COLAMD_INFO1] ++ ; 
	out_stats [COLAMD_INFO2] ++ ; 
    }
}


#ifdef MIN
#undef MIN
#endif
#define MIN(a,b) (((a) < (b)) ? (a) : (b))


static void dump_matrix
(
    Long A [ ],
    Long p [ ],
    Long n_row,
    Long n_col,
    Long Alen,
    Long limit
)
{
    Long col, k, row ;

    mexPrintf ("dump matrix: nrow %d ncol %d Alen %d\n", n_row, n_col, Alen) ;

    if (!A)
    {
    	mexPrintf ("A not present\n") ;
	return ;
    }

    if (!p)
    {
    	mexPrintf ("p not present\n") ;
	return ;
    }

    for (col = 0 ; col < MIN (n_col, limit) ; col++)
    {
	mexPrintf ("column %d, p[col] %d, p [col+1] %d, length %d\n",
		col, p [col], p [col+1], p [col+1] - p [col]) ;
    	for (k = p [col] ; k < p [col+1] ; k++)
	{
	    row = A [k] ;
	    mexPrintf (" %d", row) ;
	}
	mexPrintf ("\n") ;
    }
}
