diff --git a/processing/post/addCalculation.py b/processing/post/addCalculation.py
index 7d5de4809..5575edffd 100755
--- a/processing/post/addCalculation.py
+++ b/processing/post/addCalculation.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,damask
 from optparse import OptionParser, Option
@@ -23,17 +23,12 @@ class extendableOption(Option):
 
 
 
-def L2(object):
-
-  return math.sqrt(sum([x*x for x in object]))
-
-
 # --------------------------------------------------------------------
 #                                MAIN
 # --------------------------------------------------------------------
 
 parser = OptionParser(option_class=extendableOption, usage='%prog options [file[s]]', description = """
-Add column(s) containing norm of requested column(s) being either vectors or tensors.
+Add column(s) with derived values according to user defined arithmetic operation between column(s).
 
 """ + string.replace('$Id: addNorm.py 1118 2011-11-23 14:54:53Z MPIE\p.eisenlohr $','\n','\\n')
 )
diff --git a/processing/post/addCauchy.py b/processing/post/addCauchy.py
index 0e41b0338..9c24bedb1 100755
--- a/processing/post/addCauchy.py
+++ b/processing/post/addCauchy.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,numpy,string,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addCompatibilityMismatch.py b/processing/post/addCompatibilityMismatch.py
index a04b2cfbc..9db5cd7f1 100755
--- a/processing/post/addCompatibilityMismatch.py
+++ b/processing/post/addCompatibilityMismatch.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,numpy,DAMASK
 from optparse import OptionParser, Option
diff --git a/processing/post/addCurl.py b/processing/post/addCurl.py
index 25496b8bf..beccebb65 100755
--- a/processing/post/addCurl.py
+++ b/processing/post/addCurl.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,numpy,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addDeterminant.py b/processing/post/addDeterminant.py
index 4e237cb60..11e08bfef 100755
--- a/processing/post/addDeterminant.py
+++ b/processing/post/addDeterminant.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addDivergence.py b/processing/post/addDivergence.py
index 3b4f10471..aef507f62 100755
--- a/processing/post/addDivergence.py
+++ b/processing/post/addDivergence.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,numpy,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addMises.py b/processing/post/addMises.py
index 8790c9528..982c7d19f 100755
--- a/processing/post/addMises.py
+++ b/processing/post/addMises.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,numpy,string,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addNorm.py b/processing/post/addNorm.py
index d733a40f0..c8151f11b 100755
--- a/processing/post/addNorm.py
+++ b/processing/post/addNorm.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/addStrainTensors.py b/processing/post/addStrainTensors.py
index a4fd4866d..f7f0f4143 100755
--- a/processing/post/addStrainTensors.py
+++ b/processing/post/addStrainTensors.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,numpy,string,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/averageDown.py b/processing/post/averageDown.py
index d9202ca48..d142e1d70 100755
--- a/processing/post/averageDown.py
+++ b/processing/post/averageDown.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,string,numpy,damask
 from optparse import OptionParser, Option
diff --git a/processing/post/colormap_io.py b/processing/post/colormap_io.py
index f0681e3a7..ece42701e 100644
--- a/processing/post/colormap_io.py
+++ b/processing/post/colormap_io.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 # -*- coding: iso-8859-1 -*-
 
 def write_gsmh(RGB_vector,name):
diff --git a/processing/post/convert_colormodels.py b/processing/post/convert_colormodels.py
index 7f80a07d8..182fb816b 100644
--- a/processing/post/convert_colormodels.py
+++ b/processing/post/convert_colormodels.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 # -*- coding: iso-8859-1 -*-
 
 import math
diff --git a/processing/post/diverging_colormaps.py b/processing/post/diverging_colormaps.py
index 56ee8653f..06c0c2ce7 100644
--- a/processing/post/diverging_colormaps.py
+++ b/processing/post/diverging_colormaps.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 # -*- coding: iso-8859-1 -*-
 
 import math, convert_colormodels
diff --git a/processing/post/readResultFile.py b/processing/post/readResultFile.py
index 4f32e38bf..cb2086e3e 100644
--- a/processing/post/readResultFile.py
+++ b/processing/post/readResultFile.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 import os,re,sys,math,numpy,string
 from optparse import OptionParser, Option