#include "mex.h"

void test2();

void mexFunction( int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
    /* usage: test(M size(M,1), size(M,2)) where M is some matrix */
    /* note: plhs = left-hand side and prhs = right-hand side */

    /* initilize variables */
    mxArray *X;   /* output array object */
    double *d;    /* values of output array */
    double *data; /* values of input array */
    int m,n;      /* input matrix is m x n */
    double *t;    /* size of M variable */

    /* write message to screen */
    mexPrintf("This is a test message.\n");

    /* determine matrix dimensions */
    t = mxGetPr(prhs[1]);
    mexPrintf("The matrix has dimensionality %i x %i\n", (int)t[0], (int)t[1]);
    m = (int)t[0];
    n = (int)t[1];

    /* retrieve the input data */
    data = mxGetPr(prhs[0]);

    /* call pre-compiled code that does nothing */
    test2();

    /* prepare output matrix and data */
    X = plhs[0] = mxCreateDoubleMatrix(m, n, mxREAL);
    d = mxGetPr(X);
    /* To access the arrays, use linear indexing. */
    /* You can't use [x][y], you have to use [y+x*dimy]. */
    /* Here is an example, which we will over-write below. */
    d[0] = 17;
    d[2] = 18;
    d[1] = 19;
    d[3] = 20;
    
    /* print an element of the array */
    mexPrintf("data0 =  %g\n", data[0]);
    mexPrintf("data1 =  %g\n", data[1]);
    mexPrintf("data2 =  %g\n", data[2]);
    mexPrintf("data3 =  %g\n", data[3]);
    /* fill output matrix with input matrix minus one */
    int i,j;
    for (i=0; i<m; i++) {
        for (j=0; j<n; j++) {
            d[i+j*m] = data[i+j*m] - 1;
        }
    }
    
}