int main(int argc, char** argv) {
int m = 10;
int p = 20;
/// external allocation for the matrix
double* prD = new double[m*p];
Matrix<double> D(prD,m,p);
D.setAleat();
D.normalize();
/// Allocate a matrix of size m x p
Matrix<double> D2(m,p);
D2.setAleat();
D2.normalize();
int n = 100;
Matrix<double> X(m,n);
X.setAleat();
/// create empty sparse marix
SpMatrix<double> spa;
lasso2(X,D,spa,10,0.15); // first simple example
/// extern allocation for the matrix D requires
/// manually unallocating prD
delete[](prD);
}
virtual void run(Voxel& voxel, VoxelData& data)
{
if (!voxel.odf_decomposition)
return;
std::vector<float> old_odf(data.odf);
normalize_vector(data.odf.begin(),data.odf.end());
std::vector<float> w;
lasso2(data.odf,Rt,w,m);
std::vector<int> dir_list;
for(unsigned int index = 0;index < half_odf_size;++index)
if(w[index] > 0.0)
dir_list.push_back(index);
std::vector<float> results;
int has_isotropic = 1;
while(1)
{
if(dir_list.empty())
{
results.resize(1);
results[0] = image::mean(old_odf.begin(),old_odf.end());
has_isotropic = 1;
break;
}
std::vector<float> RRt;
if(has_isotropic)
{
RRt.resize(half_odf_size);
std::fill(RRt.begin(),RRt.end(),1.0);
}
for (unsigned int index = 0;index < dir_list.size();++index)
{
int dir = dir_list[index];
std::copy(oRt.begin()+dir*half_odf_size,
oRt.begin()+(1+dir)*half_odf_size,
std::back_inserter(RRt));
}
results.resize(dir_list.size()+has_isotropic);
image::matrix::pseudo_inverse_solve(&*RRt.begin(),&*old_odf.begin(),&*results.begin(),image::dyndim(results.size(),half_odf_size));
// drop negative
int min_index = std::min_element(results.begin()+has_isotropic,results.end())-results.begin();
if(results[min_index] < 0.0)
{
dir_list.erase(dir_list.begin()+min_index-has_isotropic);
results.erase(results.begin()+min_index);
continue;
}
if(has_isotropic && results[0] < 0.0)
{
has_isotropic = 0;
continue;
}
// drop non local maximum
std::vector<int> neighbors;
for(unsigned int i = 0;i < dir_list.size();++i)
for(unsigned int j = i+1;j < dir_list.size();++j)
if(is_neighbor[dir_list[i]][dir_list[j]])
{
neighbors.push_back(i);
neighbors.push_back(j);
}
if(neighbors.empty())
break;
int smallest_neighbor = neighbors[0];
float value = results[smallest_neighbor+has_isotropic];
for(unsigned int i = 1;i < neighbors.size();++i)
if(results[neighbors[i]+has_isotropic] < value)
{
smallest_neighbor = neighbors[i];
value = results[smallest_neighbor+has_isotropic];
}
dir_list.erase(dir_list.begin()+smallest_neighbor);
results.erase(results.begin()+smallest_neighbor+has_isotropic);
}
float fiber_sum = std::accumulate(results.begin()+has_isotropic,results.end(),0.0f);
data.min_odf = has_isotropic ? std::max<float>(results[0],0.0):0.0;
std::fill(data.odf.begin(),data.odf.end(), data.min_odf);
for(int index = 0;index < dir_list.size();++index)
data.odf[dir_list[index]] += results[index+has_isotropic];
if(data.min_odf > max_iso)
max_iso = data.min_odf;
fiber_ratio[data.voxel_index] = fiber_sum;
}