diff --git a/examples/show_butterfly.py b/examples/show_butterfly.py
old mode 100644
new mode 100755
index 2689eaa..cacbe86
--- a/examples/show_butterfly.py
+++ b/examples/show_butterfly.py
@@ -2,7 +2,7 @@
 # ==========================================================================
 # This script shows how to plot a butterfly created with ctbutterfly 
 #
-# Copyright (C) 2014 Michael Mayer
+# Copyright (C) 2014-2015 Michael Mayer
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -65,9 +65,8 @@ if __name__ == "__main__":
         butterfly_x.append(csv.real(index,0))
         low_error = csv.real(index,1)-csv.real(index,2)
         if low_error < 1e-26:
-            low_error=1e-26
+            low_error = 1e-26
         butterfly_y.append(low_error)   
-         
     
     # plot the butterfly and spectral line       
     plt.figure()
diff --git a/src/ctbutterfly/ctbutterfly.cpp b/src/ctbutterfly/ctbutterfly.cpp
index ffd30f6..4187562 100644
--- a/src/ctbutterfly/ctbutterfly.cpp
+++ b/src/ctbutterfly/ctbutterfly.cpp
@@ -36,7 +36,7 @@
 /* __ Method name definitions ____________________________________________ */
 #define G_GET_PARAMETERS                      "ctbutterfly::get_parameters()"
 #define G_SAVE                                          "ctbutterfly::save()"
-#define G_GET_MODEL_PARAMETER               "ctbutterfly::get_model_parameter()"
+#define G_GET_MODEL_PARAMETER            "ctbutterfly::get_model_parameter()"
 
 /* __ Debug definitions __________________________________________________ */
 
@@ -286,20 +286,21 @@ void ctbutterfly::run(void)
         // Loop over models
         for (int j = 0; j < models.size(); ++j) {
 
+            // If source name is found, retrieve the nominal flux
             if (models[j]->name() == m_srcname) {
 
-                // If source name is found retrieve the nominal flux
-                // Note that we have to compute the gradients here repetively to update the
-                // gradients in the vector
-                // No check for valid pointers necessary here as this was covered by get_model_parameter()
-                GModelSky* skymodel = dynamic_cast<GModelSky*>(models[j]);
+                // Note that we have to compute the gradients here
+                // repetively to update the gradients in the vector
+                // No check for valid pointers necessary here as this 
+                // was covered by get_model_parameter()
+                GModelSky*      skymodel = dynamic_cast<GModelSky*>(models[j]);
                 GModelSpectral* spectral = skymodel->spectral();
                 model_flux = spectral->eval_gradients(energy, time);
 
-          }
+            }
 
             // Loop over model parameters
-            for(int i = 0; i < models[j]->size(); ++i) {
+            for (int i = 0; i < models[j]->size(); ++i) {
 
                 // Get model parameter
                 GModelPar parameter = models[j]->at(i);
@@ -398,8 +399,8 @@ void ctbutterfly::init_members(void)
     m_ebounds.clear();
 
     // Initialise protected members
-    m_skymodel     = NULL;
-    m_par_scale    = 0.0;
+    m_skymodel  = NULL;
+    m_par_scale = 0.0;
     m_obs.clear();
     m_covariance.clear();
     m_energies.clear();
@@ -494,7 +495,7 @@ void ctbutterfly::get_parameters(void)
         std::string msg = "Source \""+m_srcname+"\" not found in model "
                           "container. Please add a source with that name "
                           "or check for possible typos.";
-    throw GException::invalid_value(G_GET_PARAMETERS, msg);
+        throw GException::invalid_value(G_GET_PARAMETERS, msg);
     }
 
     // Get relevant model and parameter for model computation
diff --git a/src/ctbutterfly/ctbutterfly.hpp b/src/ctbutterfly/ctbutterfly.hpp
index 4e24d41..f6a0c68 100644
--- a/src/ctbutterfly/ctbutterfly.hpp
+++ b/src/ctbutterfly/ctbutterfly.hpp
@@ -78,7 +78,7 @@ protected:
     void copy_members(const ctbutterfly& app);
     void free_members(void);
     void get_parameters(void);
-    void   get_model_parameter(void);
+    void get_model_parameter(void);
 
     // User parameters
     std::string m_srcname;    //!< Name of source to compute butterfly
@@ -88,8 +88,8 @@ protected:
     // Protected members
     GObservations       m_obs;        //!< Observation container
     GMatrixSparse       m_covariance; //!< Covariance matrix
-    GModelSky*    m_skymodel;     //!< Pointer to sky model
-    double    m_par_scale;    //!< Scale of normalising parameter
+    GModelSky*          m_skymodel;   //!< Pointer to sky model
+    double              m_par_scale;  //!< Scale of normalising parameter
     std::vector<double> m_energies;   //!< Energy values for storage
     std::vector<double> m_fluxes;     //!< Flux values per energy bin
     std::vector<double> m_errors;     //!< Flux errors per energy bin