ExampleMEX.cpp

This is a small example of a library that can be called from MATLAB (C) to execute a simple matrix-multipl. using the BIAS-libraries. It takes two matrices as arguments and returns the result of the multiplication.When this library has been compiled, copy it to your MATLAB-workspace and rename it to: SomeFuncName.mexglx (Linux) or SomeFuncName.dll (WIN32). Afterwards you can call the mex-file from within MATLAB using: C = SomeFuncName(A,B) (A,B initialized with matrices, C is used to store the result)

Author

apetersen

Date

07/04/2008

/* This file is part of the BIAS library (Basic ImageAlgorithmS).

   Copyright (C) 2003, 2004    (see file CONTACTS for details)
   Multimediale Systeme der Informationsverarbeitung
   Institut fuer Informatik
   Christian-Albrechts-Universitaet Kiel
   
   
   BIAS is free software; you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published by
   the Free Software Foundation; either version 2.1 of the License, or
   (at your option) any later version.
   
   BIAS is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU Lesser General Public License for more details.
   
   You should have received a copy of the GNU Lesser General Public License
   along with BIAS; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA*/

/** 
    @example ExampleMEX.cpp
    @relates MatLabInterface
    @brief This is a small example of a library that can be called from MATLAB (C) 
    to execute a simple matrix-multipl. using the BIAS-libraries. It takes two 
    matrices as arguments and returns the result of the multiplication.

    When this library has been compiled, copy it to your MATLAB-workspace and
    rename it to: SomeFuncName.mexglx (Linux) or SomeFuncName.dll (WIN32).
    Afterwards you can call the mex-file from within MATLAB using:
    C = SomeFuncName(A,B)
    (A,B initialized with matrices, C is used to store the result)
    @ingroup g_examples
    @author apetersen
    @date 07/04/2008
 */

#include <Base/Math/MatLabInterface.hh>

using namespace BIAS;

void mexFunction(//number of left-hand (output) arguments
                 int nlhs,
                 //pointer to the left-hand (output) arguments
                 mxArray *plhs[],
                 //number of right-hand (input) arguments
                 int nrhs,
                 //pointer to the right-hand (input) arguments
                 const mxArray *prhs[])
{
  //check number of input params
  if (nrhs != 2 || nlhs != 1)
    MATLABERR("Invalid argument count!");

  //convert MATLAB-data to BIAS-matrices
  Matrix<double> mat1, mat2, result;
  if (MxArrToBIASMatrix(prhs[0], mat1) != 0) {
    MATLABERR("First argument (source) is invalid!");
    return;
  }
  if (MxArrToBIASMatrix(prhs[1], mat2) != 0) {
    MATLABERR("Second argument (kernel) is invalid!");
    return;
  }

  //check if multipication is possible
  if (mat1.GetCols() != mat2.GetRows()) {
    MATLABERR("Error: invalid matrix dimensions!");
    return;
  }

  //output matrix to MATLAB-screen instead of cout/cerr!
  for (int i=0; i<3; i++) {
    for (int j=0; j<3; j++) {
      mexPrintf("mat1[%d][%d]: %f ; ", i, j, mat1[i][j]);
    }
    mexPrintf("\n");
  }

  //do multiplication
  result = mat1 * mat2;

  //convert result to MATLAB-data
  if (BIASMatrixToMxArr(result, plhs[0]) != 0) {
    MATLABERR("Error converting result to MATLAB-datatypes!");
    return;
  }

  return;
}