removed all gather from sisso regressor

src/descriptor_identifier/SISSORegressor.cpp

@@ -176,11 +176,24 @@ void SISSORegressor::l0_norm(std::vector<double>& prop, int n_dim)
     } while(util_funcs::iterate(inds, inds.size(), _mpi_comm->size()));
 
     std::vector<double> all_min_error(_mpi_comm->size() * _n_residual);
-    // std::vector<std::vector<std::vector<int>>> all_inds_min;
     std::vector<int> all_inds_min(_mpi_comm->size() *_n_residual * n_dim);
 
-    mpi::all_gather(*_mpi_comm, min_errors.data(), _n_residual, all_min_error);
-    mpi::all_gather(*_mpi_comm, inds_min.data(), _n_residual * n_dim, all_inds_min);
+    if(_mpi_comm->rank() == 0)
+    {
+        mpi::gather(*_mpi_comm, min_errors.data(), min_errors.size(), all_min_error.data(), 0);
+        mpi::broadcast(*_mpi_comm, all_min_error.data(), all_min_error.size(), 0);
+
+        mpi::gather(*_mpi_comm, inds_min.data(), inds_min.size(), all_inds_min.data(), 0);
+        mpi::broadcast(*_mpi_comm, all_inds_min.data(), all_inds_min.size(), 0);
+    }
+    else
+    {
+        mpi::gather(*_mpi_comm, min_errors.data(), min_errors.size(), 0);
+        mpi::broadcast(*_mpi_comm, all_min_error.data(), all_min_error.size(), 0);
+
+        mpi::gather(*_mpi_comm, inds_min.data(), inds_min.size(), 0);
+        mpi::broadcast(*_mpi_comm, all_inds_min.data(), all_inds_min.size(), 0);
+    }
 
     inds = util_funcs::argsort(all_min_error);