Boolean sparse reading (Scilab gateway)

How to read boolean sparse in a gateway.

Calling Sequence

Input argument profile:

SciErr getBooleanSparseMatrix(void* _pvCtx, int* _piAddress, int* _piRows, int* _piCols, int* _piNbItem, int** _piNbItemRow, int** _piColPos)

Named variable profile:

SciErr readNamedBooleanSparseMatrix(void* _pvCtx, const char* _pstName, int* _piRows, int* _piCols, int* _piNbItem, int* _piNbItemRow, int* _piColPos)

Arguments

:_pvCtx Scilab environment pointer, pass in “pvApiCtx” provided by

api_scilab.h

: :_piAddress Address of the Scilab variable. : :_pstName Name of the variable for “named” functions. : :_piRows Return number of rows of the variable. : :_piCols Return number of columns of the variable. : :_piNbItem Return number of non zero value. : :_piNbItemRow Return number of item in each rows (size: _iRows). For

“Named” function, _piNbItemRow must be allocated before calling function.

: :_piColPos Return column position for each item (size: _iNbItem).

For “Named” function, _piColPos must be allocated before calling function.

: :SciErr Error structure where is stored errors messages history and

first error number.

:

Description

This help describes how to read boolean sparse.

Gateway Source

#include "api_scilab.h"
int read_write_bsparse(char *fname,unsigned long fname_len)
{
    SciErr sciErr;
    int i                   = 0;
    int j                   = 0;
    int k                   = 0;
    //first variable info : real matrix of double
    int iRows               = 0;
    int iCols               = 0;
    int *piAddr             = NULL;
    int iNbItem             = 0;
    int* piNbItemRow        = NULL;
    int* piColPos           = NULL;
    int iCol                = 0;
    int iNewCol             = 0;
    int iNewItem            = 0;
    int* piNewRow           = NULL;
    int* piNewCol           = NULL;

    //check input and output arguments
    CheckInputArgument(pvApiCtx, 1, 1);
    CheckOutputArgument(pvApiCtx, 1, 1);

    //get variable address of the first input argument
    sciErr = getVarAddressFromPosition(pvApiCtx, 1, &piAddr);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    //get size and data from Scilab memory
    sciErr = getBooleanSparseMatrix(pvApiCtx, piAddr, &iRows, &iCols, &iNbItem, &piNbItemRow, &piColPos);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    //Do something with data
    //convert %T -> %F and %F -> %T
    iNewItem = (iRows * iCols) - iNbItem;
    piNewRow = (int*)MALLOC(sizeof(int) * iRows);
    piNewCol = (int*)MALLOC(sizeof(int) * iNewItem);

    for(i = 0 ; i < iRows ; i++)
    {
        piNewRow[i] = iCols - piNbItemRow[i];
        for(j = 0 ; j < iCols ; j++)
        {
            int iFind = 0;
            for(k = 0 ; k < piNbItemRow[i] ; k++)
            {
                if(piColPos[iCol + k] == (j + 1))
                {
                    iFind = 1;
                    break;
                }
            }

            if(iFind == 0)
            {
                piNewCol[iNewCol++] = (j + 1);
            }
        }

        iCol += piNbItemRow[i];
    }

    sciErr = createBooleanSparseMatrix(pvApiCtx, nbInputArgument + 1, iRows, iCols, iNewItem, piNewRow, piNewCol);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    AssignOutputVariable(1) = nbInputArgument + 1;
    return 0;
}

Scilab test script

a = `sparse`_([%t, %f, %t ; %f, %t, %f ; %t, %f, %t]);
a_ref = `sparse`_([%f, %t, %f ; %t, %f, %t ; %f, %t, %f]);

b = read_write_bsparse(a);
if `or`_(b <> a_ref) then `error`_("failed");end