int main(void)
{
cout << "Eigen v" << EIGEN_WORLD_VERSION << "." << EIGEN_MAJOR_VERSION << "." << EIGEN_MINOR_VERSION << endl;
static const int R = 288;
static const int N = R*(R+1)/2;
static const int M = 63;
static const int HALF_M = M/2;
static const float nsigma = 2.5f;
MatrixXf data = MatrixXf::Random(M, N);
MatrixXf mask = MatrixXf::Zero(M, N);
MatrixXf result = MatrixXf::Zero(1, N);
VectorXf std = VectorXf::Zero(N);
VectorXf centroid = VectorXf::Zero(N);
VectorXf mean = VectorXf::Zero(N);
VectorXf minval = VectorXf::Zero(N);
VectorXf maxval = VectorXf::Zero(N);
cout << "computing..." << flush;
double t = GetRealTime();
// computes the exact median
if (M&1)
{
#pragma omp parallel for
for (int i = 0; i < N; i++)
{
vector<float> row(data.data()+i*M, data.data()+(i+1)*M);
nth_element(row.begin(), row.begin()+HALF_M, row.end());
centroid(i) = row[HALF_M];
}
}
// nth_element guarantees x_0,...,x_{n-1} < x_n
else
{
#pragma omp parallel for
for (int i = 0; i < N; i++)
{
vector<float> row(data.data()+i*M, data.data()+(i+1)*M);
nth_element(row.begin(), row.begin()+HALF_M, row.end());
centroid(i) = row[HALF_M];
centroid(i) += *max_element(row.begin(), row.begin()+HALF_M);
centroid(i) *= 0.5f;
}
}
// compute the mean
mean = data.colwise().mean();
// compute std (x) = sqrt ( 1/N SUM_i (x(i) - mean(x))^2 )
std = (((data.rowwise() - mean.transpose()).array().square()).colwise().sum() *
(1.0f / M))
.array()
.sqrt();
// compute n sigmas from centroid
minval = centroid - std * nsigma;
maxval = centroid + std * nsigma;
// compute clip mask
for (int i = 0; i < N; i++)
{
mask.col(i) = (data.col(i).array() > minval(i)).select(VectorXf::Ones(M), 0.0f);
mask.col(i) = (data.col(i).array() < maxval(i)).select(VectorXf::Ones(M), 0.0f);
}
// apply clip mask to data
data.array() *= mask.array();
// compute mean such that we ignore clipped data, this is our final result
result = data.colwise().sum().array() / mask.colwise().sum().array();
t = GetRealTime() - t;
cout << "[done]" << endl << endl;
size_t bytes = data.size()*sizeof(float);
cout << "data: " << M << "x" << N << endl;
cout << "size: " << bytes*1e-6f << " MB" << endl;
cout << "rate: " << bytes/(1e6f*t) << " MB/s" << endl;
cout << "time: " << t << " s" << endl;
return 0;
}
void write_ply(const std::string &filename, const MatrixXu &F,
const MatrixXf &V, const MatrixXf &N, const MatrixXf &Nf, const MatrixXf &UV,
const MatrixXf &C, const ProgressCallback &progress) {
auto message_cb = [](p_ply ply, const char *msg) {
cerr << "rply: " << msg << endl;
};
Timer<> timer;
cout << "Writing \"" << filename << "\" (V=" << V.cols()
<< ", F=" << F.cols() << ") .. ";
cout.flush();
if (N.size() > 0 && Nf.size() > 0)
throw std::runtime_error("Please specify either face or vertex normals but not both!");
p_ply ply = ply_create(filename.c_str(), PLY_DEFAULT, message_cb, 0, nullptr);
if (!ply)
throw std::runtime_error("Unable to write PLY file!");
ply_add_comment(ply, "Generated by Instant Meshes");
ply_add_element(ply, "vertex", V.cols());
ply_add_scalar_property(ply, "x", PLY_FLOAT);
ply_add_scalar_property(ply, "y", PLY_FLOAT);
ply_add_scalar_property(ply, "z", PLY_FLOAT);
if (N.size() > 0) {
ply_add_scalar_property(ply, "nx", PLY_FLOAT);
ply_add_scalar_property(ply, "ny", PLY_FLOAT);
ply_add_scalar_property(ply, "nz", PLY_FLOAT);
if (N.cols() != V.cols() || N.rows() != 3)
throw std::runtime_error("Vertex normal matrix has incorrect size");
}
if (UV.size() > 0) {
ply_add_scalar_property(ply, "u", PLY_FLOAT);
ply_add_scalar_property(ply, "v", PLY_FLOAT);
if (UV.cols() != V.cols() || UV.rows() != 2)
throw std::runtime_error("Texture coordinate matrix has incorrect size");
}
if (C.size() > 0) {
ply_add_scalar_property(ply, "red", PLY_FLOAT);
ply_add_scalar_property(ply, "green", PLY_FLOAT);
ply_add_scalar_property(ply, "blue", PLY_FLOAT);
if (C.cols() != V.cols() || (C.rows() != 3 && C.rows() != 4))
throw std::runtime_error("Color matrix has incorrect size");
}
/* Check for irregular faces */
std::map<uint32_t, std::pair<uint32_t, std::map<uint32_t, uint32_t>>> irregular;
size_t nIrregular = 0;
if (F.rows() == 4) {
for (uint32_t f=0; f<F.cols(); ++f) {
if (F(2, f) == F(3, f)) {
nIrregular++;
auto &value = irregular[F(2, f)];
value.first = f;
value.second[F(0, f)] = F(1, f);
}
}
}
ply_add_element(ply, "face", F.cols() - nIrregular + irregular.size());
ply_add_list_property(ply, "vertex_indices", PLY_UINT8, PLY_INT);
if (Nf.size() > 0) {
ply_add_scalar_property(ply, "nx", PLY_FLOAT);
ply_add_scalar_property(ply, "ny", PLY_FLOAT);
ply_add_scalar_property(ply, "nz", PLY_FLOAT);
if (Nf.cols() != F.cols() || Nf.rows() != 3)
throw std::runtime_error("Face normal matrix has incorrect size");
}
ply_write_header(ply);
for (uint32_t j=0; j<V.cols(); ++j) {
for (uint32_t i=0; i<V.rows(); ++i)
ply_write(ply, V(i, j));
if (N.size() > 0) {
for (uint32_t i=0; i<N.rows(); ++i)
ply_write(ply, N(i, j));
}
if (UV.size() > 0) {
for (uint32_t i=0; i<UV.rows(); ++i)
ply_write(ply, UV(i, j));
}
if (C.size() > 0) {
for (uint32_t i=0; i<std::min(3u, (uint32_t) C.rows()); ++i)
ply_write(ply, C(i, j));
}
if (progress && j % 500000 == 0)
progress("Writing vertex data", j / (Float) V.cols());
}
for (uint32_t f=0; f<F.cols(); ++f) {
if (F.rows() == 4 && F(2, f) == F(3, f))
continue;
ply_write(ply, F.rows());
for (uint32_t i=0; i<F.rows(); ++i)
ply_write(ply, F(i, f));
if (Nf.size() > 0) {
for (uint32_t i=0; i<Nf.rows(); ++i)
ply_write(ply, Nf(i, f));
}
if (progress && f % 500000 == 0)
progress("Writing face data", f / (Float) F.cols());
}
for (auto item : irregular) {
auto face = item.second;
uint32_t v = face.second.begin()->first, first = v;
ply_write(ply, face.second.size());
while (true) {
ply_write(ply, v);
v = face.second[v];
if (v == first)
break;
}
if (Nf.size() > 0) {
for (uint32_t i=0; i<Nf.rows(); ++i)
ply_write(ply, Nf(i, face.first));
}
}
ply_close(ply);
cout << "done. (";
if (irregular.size() > 0)
cout << irregular.size() << " irregular faces, ";
cout << "took " << timeString(timer.value()) << ")" << endl;
}
Vector<float> as_vector (const MatrixXf & x)
{
return Vector<float>(x.size(), const_cast<float *>(x.data()));
}