// offset allows linking the data object to a sub-volume (in the z direction)
// offset is measured in floats.
CFloat32CustomMemoryMatlab3D(const mxArray* _pArray, bool bUnshare, size_t iOffset)
{
// Convert from slice to offset
mwSize dims[3];
get3DMatrixDims(_pArray, dims);
iOffset *= dims[0];
iOffset *= dims[1];
//fprintf(stderr, "Passed:\narray: %p\tdata: %p\n", (void*)_pArray, (void*)mxGetData(_pArray));
// First unshare the input array, so that we may modify it.
if (bUnshare) {
#if 0
// Unsupported in Matlab R2014b
if (mxIsSharedArray(_pArray)) {
fprintf(stderr, "Performance note: unsharing shared array in link\n");
}
#endif
mxUnshareArray(_pArray, false);
//fprintf(stderr, "Unshared:\narray: %p\tdata: %p\n", (void*)_pArray, (void*)mxGetData(_pArray));
}
// Then create a (persistent) copy so the data won't be deleted
// or changed.
m_pLink = mxCreateSharedDataCopy(_pArray);
//fprintf(stderr, "SharedDataCopy:\narray: %p\tdata: %p\n", (void*)m_pLink, (void*)mxGetData(m_pLink));
mexMakeArrayPersistent(m_pLink);
m_fPtr = (float *)mxGetData(m_pLink);
m_fPtr += iOffset;
}
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
// Check inputs
if (nrhs != 2) {
mexErrMsgIdAndTxt("Numerical:nth_element:nrhs", "Arguments should be the matrix of columns and the rank of the desired element");
}
if (!mxIsNumeric(prhs[0])) {
mexErrMsgIdAndTxt("nth_element:prhs", "First argument must be a numeric matrix.");
}
if (!mxIsNumeric(prhs[1]) || mxGetNumberOfDimensions(prhs[1]) != 2 || mxGetM(prhs[1]) != 1 || mxGetN(prhs[1]) != 1) {
mexErrMsgIdAndTxt("nth_element:prhs", "Second argument must be a scalar.");
}
const mwSize nrows = mxGetM(prhs[0]);
const mwSize ncols = mxGetN(prhs[0]);
// Validate rank argument
mwIndex rank = (mwIndex) mxGetScalar(prhs[1]);
if (rank < 1) {
mexErrMsgIdAndTxt("nth_element:prhs", "Rank cannot be less than 1.");
}
if (rank > nrows) {
mexErrMsgIdAndTxt("nth_element:prhs", "Rank cannot be greater than the number of rows.");
}
// Convert matlab-style index (starts at 1) to C++ (starts at 0).
rank--;
// If user wants to also get the rearranged indices, have to do extra work
unsigned int *indices;
if (nlhs > 1) {
plhs[1] = mxCreateNumericMatrix(nrows, ncols, mxUINT32_CLASS, mxREAL);
indices = (unsigned int *) mxGetData(plhs[1]);
for (mwIndex i = 0; i < ncols; ++i) {
for (mwIndex j = 0; j < nrows; ++j) indices[i*nrows + j] = j;
}
}
// Unshare input array if necessary, then modify inplace. UNDOCUMENTED CALLS!!
plhs[0] = (mxArray*) prhs[0];
mxUnshareArray(plhs[0], true);
if (nlhs > 1) {
run_nth_element(plhs[0], indices, rank, ncols, nrows);
for (mwIndex i = 0; i < ncols*nrows; ++i) ++indices[i]; // Fix for janky Matlab 1-indexing
} else {
run_nth_element(plhs[0], rank, ncols, nrows);
}
}
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {
// Check inputs
if (nrhs != 1) {
mexErrMsgIdAndTxt("Numerical:fast_median:nrhs", "Arguments should be the matrix of columns and the rank of the desired element");
}
if (!mxIsNumeric(prhs[0])) {
mexErrMsgIdAndTxt("Numerical:fast_median:prhs", "Input argument must be a numeric matrix.");
}
// Unshare input array if necessary, then modify inplace. UNDOCUMENTED MEX CALLS!!
plhs[0] = (mxArray*) prhs[0];
mxUnshareArray(plhs[0], true);
plhs[0] = run_fast_median(plhs[0]);
}
