diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bee8a64
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+__pycache__
diff --git a/src/bdump.py b/src/bdump.py
index ac75c04..2a67860 100644
--- a/src/bdump.py
+++ b/src/bdump.py
@@ -68,11 +68,9 @@
 #     atoms[i][j] = 2d array of floats, i = 0 to natoms-1, j = 0 to ncols-1
 
 try:
-    import numpy as np
-    oldnumeric = False
+  import numpy as np
 except:
-    import Numeric as np
-    oldnumeric = True
+  raise Exception("no numpy Python module available")
 
 try: from DEFAULTS import PIZZA_GUNZIP
 except: PIZZA_GUNZIP = "gunzip"
@@ -188,8 +186,7 @@ def read_snapshot(self,f):
         for i in range(1,snap.natoms):
           words += f.readline().split()
         floats = list(map(float,words))
-        if oldnumeric: atoms = np.zeros((snap.natoms,ncol),np.Float)
-        else: atoms = np.zeros((snap.natoms,ncol),np.float)
+        atoms = np.zeros((snap.natoms,ncol),float)
         start = 0
         stop = ncol
         for i in range(snap.natoms):
diff --git a/src/dump.py b/src/dump.py
index 6d6280b..5e9f3f4 100644
--- a/src/dump.py
+++ b/src/dump.py
@@ -191,10 +191,8 @@
 
 try:
   import numpy as np
-  oldnumeric = False
 except:
-  import Numeric as np
-  oldnumeric = True
+  raise Exception("no numpy Python module available")
 
 try: from DEFAULTS import PIZZA_GUNZIP
 except: PIZZA_GUNZIP = "gunzip"
@@ -418,8 +416,7 @@ def read_snapshot(self,f):
         for i in range(1,snap.natoms):
           words += f.readline().split()
         floats = list(map(float,words))
-        if oldnumeric: atoms = np.zeros((snap.natoms,ncol),np.Float)
-        else: atoms = np.zeros((snap.natoms,ncol),np.float)
+        atoms = np.zeros((snap.natoms,ncol),float)
         start = 0
         stop = ncol
         for i in range(snap.natoms):
@@ -887,8 +884,7 @@ def newcolumn(self,str):
     self.map(ncol+1,str)
     for snap in self.snaps:
       atoms = snap.atoms
-      if oldnumeric: newatoms = np.zeros((snap.natoms,ncol+1),np.Float)
-      else: newatoms = np.zeros((snap.natoms,ncol+1),np.float)
+      newatoms = np.zeros((snap.natoms,ncol+1),float)
       newatoms[:,0:ncol] = snap.atoms
       snap.atoms = newatoms
 
diff --git a/src/ldump.py b/src/ldump.py
index 8660afe..a30d7eb 100644
--- a/src/ldump.py
+++ b/src/ldump.py
@@ -75,11 +75,9 @@
 #     atoms[i][j] = 2d array of floats, i = 0 to natoms-1, j = 0 to ncols-1
 
 try:
-    import numpy as np
-    oldnumeric = False
+  import numpy as np
 except:
-    import Numeric as np
-    oldnumeric = True
+  raise Exception("no numpy Python module available")
 
 try: from DEFAULTS import PIZZA_GUNZIP
 except: PIZZA_GUNZIP = "gunzip"
@@ -202,8 +200,7 @@ def read_snapshot(self,f):
         for i in range(1,snap.natoms):
           words += f.readline().split()
         floats = list(map(float,words))
-        if oldnumeric: atoms = np.zeros((snap.natoms,ncol),np.Float)
-        else: atoms = np.zeros((snap.natoms,ncol),np.float)
+        atoms = np.zeros((snap.natoms,ncol),float)
         start = 0
         stop = ncol
         for i in range(snap.natoms):
diff --git a/src/mdump.py b/src/mdump.py
index 714add5..37aa5df 100644
--- a/src/mdump.py
+++ b/src/mdump.py
@@ -133,11 +133,9 @@
 #     evalues[i][j] = 2d array of floats, i = 0 to Nel-1, j = 0 to Ncol
 
 try:
-    import numpy as np
-    oldnumeric = False
+  import numpy as np
 except:
-    import Numeric as np
-    oldnumeric = True
+  raise Exception("no numpy Python module available")
 
 try: from DEFAULTS import PIZZA_GUNZIP
 except: PIZZA_GUNZIP = "gunzip"
@@ -318,8 +316,7 @@ def read_snapshot(self,f):
         for i in range(1,n):
           words += f.readline().split()
         floats = list(map(float,words))
-        if oldnumeric: values = np.zeros((n,ncol),np.Float)
-        else: values = np.zeros((n,ncol),np.float)
+        values = np.zeros((n,ncol),float)
         start = 0
         stop = ncol
         for i in range(n):
diff --git a/src/tdump.py b/src/tdump.py
index 711551e..b151229 100644
--- a/src/tdump.py
+++ b/src/tdump.py
@@ -76,11 +76,9 @@
 #     atoms[i][j] = 2d array of floats, i = 0 to natoms-1, j = 0 to ncols-1
 
 try:
-    import numpy as np
-    oldnumeric = False
+  import numpy as np
 except:
-    import Numeric as np
-    oldnumeric = True
+  raise Exception("no numpy Python module available")
 
 try: from DEFAULTS import PIZZA_GUNZIP
 except: PIZZA_GUNZIP = "gunzip"
@@ -203,8 +201,7 @@ def read_snapshot(self,f):
         for i in range(1,snap.natoms):
           words += f.readline().split()
         floats = list(map(float,words))
-        if oldnumeric: atoms = np.zeros((snap.natoms,ncol),np.Float)
-        else: atoms = np.zeros((snap.natoms,ncol),np.float)
+        atoms = np.zeros((snap.natoms,ncol),float)
         start = 0
         stop = ncol
         for i in range(snap.natoms):
diff --git a/src/vtk.py b/src/vtk.py
index 96c2dc7..83f4590 100644
--- a/src/vtk.py
+++ b/src/vtk.py
@@ -346,7 +346,8 @@ def particleGran(file,atoms,names,n_values):
       continue
 
     vectortype = 'float'
-    if atoms != []:
+    #if atoms != []:
+    if atoms.size > 0:
       vectortype = typestr(atoms[0][vectors[key]])
       if 'float' in vectortype: vectortype = 'float'
       elif 'int' in vectortype: vectortype = 'int'
@@ -361,7 +362,8 @@ def particleGran(file,atoms,names,n_values):
   # print SCALARS
   for key in scalars.keys():
     scalartype =''
-    if atoms != []:
+    #if atoms != []:
+    if atoms.size > 0:
       scalartype = typestr(atoms[0][scalars[key]])
       if 'float' in scalartype: scalartype = 'float'
       elif 'int' in scalartype: scalartype = 'int'