diff --git a/src/OpenMesh/Core/IO/reader/PLYReader.cc b/src/OpenMesh/Core/IO/reader/PLYReader.cc
index cd089f53..e456d24c 100644
--- a/src/OpenMesh/Core/IO/reader/PLYReader.cc
+++ b/src/OpenMesh/Core/IO/reader/PLYReader.cc
@@ -859,7 +859,6 @@ bool _PLYReader_::can_u_read(std::istream& _is) const {
     std::string keyword;
     std::string fileType;
     std::string elementName = "";
-    std::string propertyType;
     std::string propertyName;
     std::string listIndexType;
     std::string listEntryType;
diff --git a/src/OpenMesh/Tools/Utils/Gnuplot.cc b/src/OpenMesh/Tools/Utils/Gnuplot.cc
index 0ab66af3..1938867e 100644
--- a/src/OpenMesh/Tools/Utils/Gnuplot.cc
+++ b/src/OpenMesh/Tools/Utils/Gnuplot.cc
@@ -129,7 +129,7 @@ Gnuplot::Gnuplot(const string &title,
 {
   init();
 		
-  if (x.size() == 0 || y.size() == 0)
+  if (x.empty() || y.empty() )
     throw GnuplotException("vectors too small");
   
   if (style == "")
@@ -160,7 +160,7 @@ Gnuplot::Gnuplot(const string &title,  const string &style,
 {
   init();
   
-  if (x.size() == 0)
+  if (x.empty() )
     throw GnuplotException("vector too small");
   if (!this->gnucmd)
     throw GnuplotException("Could'nt open connection to gnuplot");
@@ -189,7 +189,7 @@ Gnuplot::Gnuplot(const string &title,  const string &style,
 
 Gnuplot::~Gnuplot()
 {
-  if ((this->to_delete).size() > 0)
+  if ( !((this->to_delete).empty()) )
   {
     for (size_t i = 0; i < this->to_delete.size(); i++)
       remove(this->to_delete[i].c_str());
@@ -228,7 +228,7 @@ bool Gnuplot::get_program_path(const string pname)
 
 void Gnuplot::reset_plot(void)
 {       
-  if (this->to_delete.size() > 0)
+  if ( !(this->to_delete.empty()) )
   {
     for (size_t i = 0; i < this->to_delete.size(); i++)
       remove(this->to_delete[i].c_str());