From 435680b57e5595ed32ae491254ffad7a7877ab0f Mon Sep 17 00:00:00 2001
From: euklid <r@twopi.eu>
Date: Sat, 22 Aug 2015 16:40:02 +0200
Subject: [PATCH] important bug fix (never forget to initialize...) and further
 tweaks

---
 fmm2d.cpp                   | 8 ++++++++
 kernel_laplace_point_2d.cpp | 2 +-
 main.cpp                    | 2 +-
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/fmm2d.cpp b/fmm2d.cpp
index b35b1f8..2226eb8 100644
--- a/fmm2d.cpp
+++ b/fmm2d.cpp
@@ -67,6 +67,10 @@ void FMM2D::upward_pass()
 #endif
 
         // leaf node has to calculate its moments
+        if(cur_cell->get_source_elements().empty()) 
+        {
+            continue;
+        }
         if (cur_cell->is_leaf())
         {
             std::vector<complex_t> moments = m_kernel->calc_moments_cmp(cur_cell->get_source_elements(),
@@ -128,6 +132,10 @@ void FMM2D::m2l_downward_pass(Cell* cur_cell)
     for(unsigned int i = 0; i<num_interaction_list; i++)
     {
         std::vector<complex_t> shifted_moments(m_loc_terms,0);
+        if(interaction_list[i]->get_source_elements().empty())
+        {
+            continue;
+        }
         m_kernel->M2L_cmp(interaction_list[i]->get_moments_cmp(),
                           interaction_list[i]->get_center(),
                           shifted_moments,
diff --git a/kernel_laplace_point_2d.cpp b/kernel_laplace_point_2d.cpp
index 37ad887..704ff2f 100644
--- a/kernel_laplace_point_2d.cpp
+++ b/kernel_laplace_point_2d.cpp
@@ -131,7 +131,7 @@ complex_t Laplace2DKernel::L2element_cmp(const std::vector<complex_t> &local_in,
 {
     complex_t dist = (complex_t)el.get_position() - local_center;
     unsigned int num_local_exp = local_in.size();
-    complex_t fac;
+    complex_t fac(1,0);
     complex_t res = local_in[0];
     for(int i = 1; i<num_local_exp; i++)
     {
diff --git a/main.cpp b/main.cpp
index 1565b36..d0feb8b 100644
--- a/main.cpp
+++ b/main.cpp
@@ -209,7 +209,7 @@ int main(int argc, char** argv)
     unsigned int num_tgts = direct_val.size();
     for(int i = 0; i<num_tgts; i++)
     {
-        std::cout << "diff: dir: " << direct_val[i] <<" fmm: " << tgt_elements[i]->get_target_value() << std::endl;
+        std::cout << "diff: dir: " << direct_val[i] <<" fmm: " << tgt_elements[i]->get_target_value() << " diff: " << direct_val[i]-tgt_elements[i]->get_target_value() << std::endl;
     }
 #endif
     std::cout << "Hello World!" << std::endl;