diff --git a/examples/psystem_2d/psystem_2d.py b/examples/psystem_2d/psystem_2d.py
index 9d9b67ea7..fdb46040b 100755
--- a/examples/psystem_2d/psystem_2d.py
+++ b/examples/psystem_2d/psystem_2d.py
@@ -141,8 +141,8 @@ def setup(kernel_language='Fortran',
     x_lower=0.25; x_upper=20.25
     y_lower=0.25; y_upper=20.25
     # cells per layer
-    mx=(x_upper-x_lower)*cells_per_layer; 
-    my=(y_upper-y_lower)*cells_per_layer
+    mx=int((x_upper-x_lower)*cells_per_layer)
+    my=int((y_upper-y_lower)*cells_per_layer)
     # Initial condition parameters
     initial_amplitude=10.
     x0=0.25 # Center of initial perturbation
diff --git a/src/pyclaw/geometry.py b/src/pyclaw/geometry.py
index efd6152ca..1430daa02 100644
--- a/src/pyclaw/geometry.py
+++ b/src/pyclaw/geometry.py
@@ -470,7 +470,7 @@ class Dimension(object):
     
     :Initialization:
     
-    Required arguments, order:
+    Required arguments, in order:
      - *lower* - (float) Lower extent of dimension
      - *upper* - (float) Upper extent of dimension
      - *num_cells* - (int) Number of cells
@@ -578,52 +578,36 @@ def edges_with_ghost(self,num_ghost):
         return np.hstack((pre,edges,post))
 
     
-    def __init__(self, *args, **kargs):
+    def __init__(self, lower, upper, num_cells, name='x',
+                 on_lower_boundary=None,on_upper_boundary=None, units=None):
         r"""
         Create a Dimension object.
-        
+
         See :class:`Dimension` for full documentation
         """
-        
-        # ========== Class Data Attributes ===================================
-        self.name = 'x'
-        r"""(string) Name of this coordinate dimension (e.g. 'x')"""
-        self.on_lower_boundary = None
-        r"""(bool) - Whether the dimension is touching a lower boundary."""
-        self.on_upper_boundary = None
-        r"""(bool) - Whether the dimension is touching an upper boundary."""
-        self.units = None
-        r"""(string) Corresponding physical units of this dimension (e.g. 
-        'm/s'), ``default = None``"""
+        if isinstance(lower,basestring):
+            raise Exception('Passing dimension name as first argument is deprecated. \
+                             Pass it as a keyword argument instead.')
 
         self._edges = None
         self._centers = None
         self._centers_with_ghost = None
         self._edges_with_ghost = None
 
-        # Parse args
-        if isinstance(args[0],basestring):
-            import warnings
-            warnings.warn('Passing dimension name as first argument is deprecated. \
-                           Pass it as a keyword argument instead.')
-            self.name = args[0]
-            self._lower = float(args[1])
-            self._upper = float(args[2])
-            self._num_cells = int(args[3])
-        else:
-            self._lower = float(args[0])
-            self._upper = float(args[1])
-            self._num_cells = int(args[2])
-        
-        for (k,v) in kargs.iteritems():
-            setattr(self,k,v)
+        self._lower = float(lower)
+        self._upper = float(upper)
+        self._num_cells = int(num_cells)
+        self.name = name
+        self.on_lower_boundary = on_lower_boundary
+        self.on_upper_boundary = on_upper_boundary
+        self.units = units
 
         self._check_validity()
 
     def _check_validity(self):
-        assert type(self.num_cells) is int, 'Dimension.num_cells must be an integer'
-        assert type(self.lower) is float, 'Dimension.lower must be a float'
-        assert type(self.upper) is float, 'Dimension.upper must be a float'
+        assert isinstance(self.num_cells,int), 'Dimension.num_cells must be an integer; got %s' % type(self.num_cells)
+        assert isinstance(self.lower,float), 'Dimension.lower must be a float'
+        assert isinstance(self.upper,float), 'Dimension.upper must be a float'
         assert self.num_cells>0, 'Dimension.num_cells must be positive'
         assert self.upper > self.lower, 'Dimension.upper must be greater than lower'
 
diff --git a/src/pyclaw/io/ascii.py b/src/pyclaw/io/ascii.py
index 428310451..c4d2e581e 100755
--- a/src/pyclaw/io/ascii.py
+++ b/src/pyclaw/io/ascii.py
@@ -168,7 +168,7 @@ def read(solution,frame,path='./',file_prefix='fort',read_aux=False,
     [t,num_eqn,nstates,num_aux,num_dim] = read_t(frame,path,file_prefix)
 
     patches = []
-    n = np.zeros((num_dim))
+    n = np.zeros((num_dim),dtype=int)
     d = np.zeros((num_dim))
     lower = np.zeros((num_dim))
     # Since we do not have names here, we will construct each patch with
diff --git a/src/pyclaw/io/binary.py b/src/pyclaw/io/binary.py
index 6342e1adf..9e2c7594c 100755
--- a/src/pyclaw/io/binary.py
+++ b/src/pyclaw/io/binary.py
@@ -58,7 +58,7 @@ def read(solution,frame,path='./',file_prefix='fort',read_aux=False,
         qdata = np.fromfile(file=b_file, dtype=np.float64)
 
     i_start_patch = 0  # index into qdata for start of next patch
-    n     = np.zeros((num_dim))
+    n     = np.zeros((num_dim),dtype=int)
     lower = np.zeros((num_dim))
     d     = np.zeros((num_dim))
     # Since we do not have dimension names here, we will construct
diff --git a/src/pyclaw/util.py b/src/pyclaw/util.py
index 78d926584..510f82f55 100755
--- a/src/pyclaw/util.py
+++ b/src/pyclaw/util.py
@@ -536,12 +536,12 @@ def read_data_line(inputfile,num_entries=1,data_type=float):
     while  l==[]:  # skip over blank lines
         line = inputfile.readline()
         l = line.split()
+    if num_entries == 1:  # This is a convenience for calling functions
+        return data_type(l[0])
     val = np.empty(num_entries,data_type)
     if num_entries > len(l):
         print 'Error in read_data_line: num_entries = ', num_entries
         print '  is larger than length of l = ',l
-    if num_entries == 1:  # This is a convenience for calling functions
-        return data_type(l[0])
     val = [data_type(entry) for entry in l[:num_entries]]
     return val