Changeset 2778 for trunk

Timestamp:

10/23/2008 04:43:14 PM (3 months ago)

Author:

guyer

Message:

Merged log:branches/abstractBaseClass@2774:2775 via svnmerge to source:trunk

........

r2774 | guyer | 2008-10-23 16:00:35 -0400 (Thu, 23 Oct 2008) | 2 lines

raise NotImplementedError for abstract bases

........

r2775 | guyer | 2008-10-23 16:20:53 -0400 (Thu, 23 Oct 2008) | 2 lines

can't test abstract bases

........

Location:

trunk

Files:

• . (modified) (1 prop)
• FiPy.egg-info/SOURCES.txt (modified) (1 diff)
• fipy/boundaryConditions/boundaryCondition.py (modified) (6 diffs)
• fipy/solvers/pysparse/pysparseSolver.py (modified) (2 diffs)
• fipy/solvers/scipy/scipySolver.py (modified) (2 diffs)
• fipy/solvers/solver.py (modified) (4 diffs)
• fipy/solvers/trilinos/preconditioners/preconditioner.py (modified) (2 diffs)
• fipy/solvers/trilinos/trilinosAztecOOSolver.py (modified) (2 diffs)
• fipy/solvers/trilinos/trilinosSolver.py (modified) (3 diffs)
• fipy/terms/cellTerm.py (modified) (4 diffs)
• fipy/terms/convectionTerm.py (modified) (5 diffs)
• fipy/terms/equation.py (modified) (4 diffs)
• fipy/terms/faceTerm.py (modified) (2 diffs)
• fipy/terms/sourceTerm.py (modified) (2 diffs)
• fipy/terms/term.py (modified) (12 diffs)
• fipy/variables/noiseVariable.py (modified) (2 diffs)
• fipy/viewers/gistViewer/gistViewer.py (modified) (2 diffs)
• fipy/viewers/gnuplotViewer/gnuplotViewer.py (modified) (2 diffs)
• fipy/viewers/matplotlibViewer/matplotlibViewer.py (modified) (2 diffs)
• fipy/viewers/viewer.py (modified) (2 diffs)

trunk/FiPy.egg-info/SOURCES.txt

@@ -501 +501 @@
 utils/includedHTMLWriter.py
 utils/includedLaTeXWriter.py
-utils/epydoc/Makefile
-utils/epydoc/doc/.cvsignore
-utils/epydoc/doc/configfile.html
-utils/epydoc/doc/custom.css
-utils/epydoc/doc/docstrings.html
-utils/epydoc/doc/docutils.css
-utils/epydoc/doc/epydoc-slides.pdf
-utils/epydoc/doc/epydoc-slides.ppt
-utils/epydoc/doc/epydoc.css
-utils/epydoc/doc/epydoc_gui.png
-utils/epydoc/doc/epydoc_guiconfig.png
-utils/epydoc/doc/epytext.html
-utils/epydoc/doc/epytext_example.py
-utils/epydoc/doc/epytextintro.html
-utils/epydoc/doc/faq.html
-utils/epydoc/doc/fields.html
-utils/epydoc/doc/future.html
-utils/epydoc/doc/history.html
-utils/epydoc/doc/home.thumbnail.png
-utils/epydoc/doc/index.html
-utils/epydoc/doc/index.thumbnail.png
-utils/epydoc/doc/inh_example.py
-utils/epydoc/doc/installing.html
-utils/epydoc/doc/license.html
-utils/epydoc/doc/manual-docstring.txt
-utils/epydoc/doc/manual-epytext.txt
-utils/epydoc/doc/manual-fields.txt
-utils/epydoc/doc/manual-install.txt
-utils/epydoc/doc/manual-othermarkup.txt
-utils/epydoc/doc/manual-reference.txt
-utils/epydoc/doc/manual-usage.txt
-utils/epydoc/doc/manual.txt
-utils/epydoc/doc/othermarkup.html
-utils/epydoc/doc/pycon-epydoc.html
-utils/epydoc/doc/pycon-epydoc.pdf
-utils/epydoc/doc/pycon-epydoc.ps
-utils/epydoc/doc/pysrc.thumbnail.png
-utils/epydoc/doc/relatedprojects.html
-utils/epydoc/doc/rst-template.txt
-utils/epydoc/doc/rst-template2.txt
-utils/epydoc/doc/sflogo.png
-utils/epydoc/doc/stylesheet.html
-utils/epydoc/doc/uml.thumbnail.png
-utils/epydoc/doc/using.html
-utils/epydoc/doc/whatsnew.html
-utils/epydoc/doc/doctest/index.html
-utils/epydoc/man/epydoc.1
-utils/epydoc/man/epydocgui.1
-utils/epydoc/src/LICENSE.txt
-utils/epydoc/src/MANIFEST.in
-utils/epydoc/src/Makefile
-utils/epydoc/src/README.txt
-utils/epydoc/src/setup.py
-utils/epydoc/src/epydoc/__init__.py
-utils/epydoc/src/epydoc/apidoc.py
-utils/epydoc/src/epydoc/checker.py
-utils/epydoc/src/epydoc/cli.py
-utils/epydoc/src/epydoc/compat.py
-utils/epydoc/src/epydoc/docbuilder.py
-utils/epydoc/src/epydoc/docintrospecter.py
-utils/epydoc/src/epydoc/docparser.py
-utils/epydoc/src/epydoc/docstringparser.py
-utils/epydoc/src/epydoc/gui.py
-utils/epydoc/src/epydoc/log.py
-utils/epydoc/src/epydoc/util.py
-utils/epydoc/src/epydoc/docwriter/__init__.py
-utils/epydoc/src/epydoc/docwriter/dotgraph.py
-utils/epydoc/src/epydoc/docwriter/html.py
-utils/epydoc/src/epydoc/docwriter/html_colorize.py
-utils/epydoc/src/epydoc/docwriter/html_css.py
-utils/epydoc/src/epydoc/docwriter/html_help.py
-utils/epydoc/src/epydoc/docwriter/latex.py
-utils/epydoc/src/epydoc/docwriter/plaintext.py
-utils/epydoc/src/epydoc/docwriter/xlink.py
-utils/epydoc/src/epydoc/docwriter/latexstyles/epydoc-default.sty
-utils/epydoc/src/epydoc/markup/__init__.py
-utils/epydoc/src/epydoc/markup/doctest.py
-utils/epydoc/src/epydoc/markup/epytext.py
-utils/epydoc/src/epydoc/markup/javadoc.py
-utils/epydoc/src/epydoc/markup/plaintext.py
-utils/epydoc/src/epydoc/markup/pyval_repr.py
-utils/epydoc/src/epydoc/markup/restructuredtext.py
-utils/epydoc/src/epydoc/test/__init__.py
-utils/epydoc/src/epydoc/test/apidoc.doctest
-utils/epydoc/src/epydoc/test/docbuilder.doctest
-utils/epydoc/src/epydoc/test/docintrospecter.doctest
-utils/epydoc/src/epydoc/test/docparser.doctest
-utils/epydoc/src/epydoc/test/encoding.doctest
-utils/epydoc/src/epydoc/test/epytext.doctest
-utils/epydoc/src/epydoc/test/javadoc.doctest
-utils/epydoc/src/epydoc/test/plaintext.doctest
-utils/epydoc/src/epydoc/test/pyval_repr.doctest
-utils/epydoc/src/epydoc/test/restructuredtext.doctest
-utils/epydoc/src/epydoc/test/util.py
-utils/epydoc/src/epydoc/test/zope2.doctest
-utils/epydoc/src/epydoc/test/zope3.doctest
-utils/epydoc/src/scripts/.cvsignore
-utils/epydoc/src/scripts/apirst2html.py
-utils/epydoc/src/scripts/epydoc
-utils/epydoc/src/scripts/epydoc.py
-utils/epydoc/src/scripts/epydoc.pyw
-utils/epydoc/src/scripts/epydocgui
-utils/epydoc/src/tools/mkdispatch.py
-utils/epydoc/src/tools/rst2html.py

trunk/fipy/boundaryConditions/boundaryCondition.py

@@ -7 +7 @@
  #  FILE: "boundaryCondition.py"
  #                                    created: 11/15/03 {9:47:59 PM} 
- #                                last update: 6/2/08 {10:41:16 PM} 
+ #                                last update: 10/23/08 {4:11:11 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -56 +56 @@
     def __init__(self,faces,value):
         """
-
-        The `BoundaryCondition` class should not be invoked directly.
-        
         :Parameters:
             - `faces`: A `list` or `tuple` of `Face` objects to which this condition applies.
@@ -69 +66 @@
             >>> from fipy.meshes.grid1D import Grid1D
             >>> mesh = Grid1D(nx = 2)
-            >>> bc = BoundaryCondition(mesh.getInteriorFaces(), 0)
+            >>> bc = __BoundaryCondition(mesh.getInteriorFaces(), 0)
             Traceback (most recent call last):
                 ...
@@ -75 +72 @@
 
         """
+        if self.__class__ is BoundaryCondition:
+            raise NotImplementedError, "can't instantiate abstract base class"
+        
         self.faces = faces
         self.value = PhysicalField(value)
@@ -100 +100 @@
         (**L**, **b**) matrices.
         """ 
-        pass
+        raise NotImplementedError
     
     def _getDerivative(self, order):
@@ -117 +117 @@
         self.boundaryConditionApplied = False
 
+class __BoundaryCondition(BoundaryCondition): 
+    """
+    Dummy subclass for tests
+    """
+    pass 
+
 def _test(): 
     import doctest

trunk/fipy/solvers/pysparse/pysparseSolver.py

@@ -8 +8 @@
  #  FILE: "pysparseSolver.py"
  #                                    created: 06/28/07
- #                                last update: 06/28/07
+ #                                last update: 10/23/08 {3:04:27 PM}
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -53 +53 @@
     .. attention:: This class is abstract. Always create one of its subclasses.
     """
+    def __init__(self, *args, **kwargs):
+        if self.__class__ is PysparseSolver:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
+        Solver.__init__(self, *args, **kwargs)
 
     def _getMatrixClass(self):

trunk/fipy/solvers/scipy/scipySolver.py

@@ -8 +8 @@
  #  FILE: "scipySolver.py"
  #                                    created: 06/28/07
- #                                last update: 06/29/07
+ #                                last update: 10/23/08 {3:05:25 PM}
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -53 +53 @@
     .. attention:: This class is abstract. Always create one of its subclasses.
     """
+    def __init__(self, *args, **kwargs):
+        if self.__class__ is ScipySolver:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
+        Solver.__init__(self, *args, **kwargs)
 
     def _getMatrixClass(self):

trunk/fipy/solvers/solver.py

@@ -8 +8 @@
  #  FILE: "solver.py"
  #                                    created: 11/14/03 {3:47:20 PM} 
- #                                last update: 11/16/06 {2:36:00 PM} 
+ #                                last update: 10/23/08 {3:02:19 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -111 +111 @@
 
         """
+        if self.__class__ is Solver:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         self.tolerance = tolerance
         if steps is not None:
@@ -126 +129 @@
         
     def _solve(self, L, x, b):
-        pass
+        raise NotImplementedError
         
     _warningList = (ScalarQuantityOutOfRangeWarning,
@@ -152 +155 @@
 
     def _getMatrixClass(self):
-        pass
+        raise NotImplementedError

trunk/fipy/solvers/trilinos/preconditioners/preconditioner.py

@@ -8 +8 @@
  #  FILE: "preconditioner.py"
  #                                    created: 06/25/07
- #                                last update: 06/25/07
+ #                                last update: 10/23/08 {3:07:49 PM}
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -56 +56 @@
         Create a `Preconditioner` object.
         """
-        pass
+        if self.__class__ is Preconditioner:
+            raise NotImplementedError, "can't instantiate abstract base class"
         
     def _applyToSolver(self, solver, matrix):
-        pass
+        raise NotImplementedError
         

trunk/fipy/solvers/trilinos/trilinosAztecOOSolver.py

@@ -7 +7 @@
  #  FILE: "trilinosAztecOOSolver.py"
  #                                    created: 06/25/07 
- #                                last update: 06/25/07 
+ #                                last update: 10/23/08 {3:10:10 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -65 +65 @@
 
         """
+        if self.__class__ is TrilinosAztecOOSolver:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         TrilinosSolver.__init__(self, tolerance=tolerance,
                                 iterations=iterations, steps=steps, precon=None)

trunk/fipy/solvers/trilinos/trilinosSolver.py

@@ -7 +7 @@
  #  FILE: "trilinosSolver.py"
  #                                    created: 06/07/07 
- #                                last update: 06/25/07 
+ #                                last update: 10/23/08 {3:10:07 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -60 +60 @@
 
     """
-    
+    def __init__(self, *args, **kwargs):
+        if self.__class__ is TrilinosSolver:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
     def _makeTrilinosMatrix(self, L):
         """ 
@@ -132 +135 @@
 
     def _applyTrilinosSolver(self):
-        pass
+        raise NotImplementedError

trunk/fipy/terms/cellTerm.py

@@ -7 +7 @@
  #  FILE: "cellTerm.py"
  #                                    created: 11/12/03 {11:00:54 AM} 
- #                                last update: 3/29/07 {10:40:50 AM} 
+ #                                last update: 10/23/08 {4:04:47 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -55 +55 @@
     """
     def __init__(self, coeff=1.):
+        if self.__class__ is CellTerm:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         from fipy.variables.variable import Variable
         if not isinstance(coeff, Variable):
@@ -158 +161 @@
             >>> vcv = CellVariable(mesh=m, rank=1)
             >>> vfv = FaceVariable(mesh=m, rank=1)
-            >>> CellTerm(coeff=cv)
-            CellTerm(coeff=CellVariable(value=array([ 0.,  0.]), mesh=UniformGrid1D(dx=1.0, nx=2)))
-            >>> CellTerm(coeff=1)
-            CellTerm(coeff=1)
-            >>> CellTerm(coeff=fv)
-            Traceback (most recent call last):
-                ...
-            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
-            >>> CellTerm(coeff=vcv)
-            Traceback (most recent call last):
-                ...
-            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
-            >>> CellTerm(coeff=vfv)
-            Traceback (most recent call last):
-                ...
-            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
-            >>> CellTerm(coeff=(1,))
+
+            >>> __CellTerm(coeff=cv)
+            __CellTerm(coeff=CellVariable(value=array([ 0.,  0.]), mesh=UniformGrid1D(dx=1.0, nx=2)))
+            >>> __CellTerm(coeff=1)
+            __CellTerm(coeff=1)
+            >>> __CellTerm(coeff=fv)
+            Traceback (most recent call last):
+                ...
+            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
+            >>> __CellTerm(coeff=vcv)
+            Traceback (most recent call last):
+                ...
+            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
+            >>> __CellTerm(coeff=vfv)
+            Traceback (most recent call last):
+                ...
+            TypeError: The coefficient must be a rank-0 CellVariable or a scalar value.
+            >>> __CellTerm(coeff=(1,))
             Traceback (most recent call last):
                 ...
@@ -182 +186 @@
         pass
 
+class __CellTerm(CellTerm):
+    """
+    Dummy subclass for tests
+    """
+    pass 
+    
 
 def _test(): 

trunk/fipy/terms/convectionTerm.py

@@ -7 +7 @@
  #  FILE: "convectionTerm.py"
  #                                    created: 11/13/03 {11:39:03 AM} 
- #                                last update: 3/29/07 {10:40:48 AM} 
+ #                                last update: 10/23/08 {4:07:28 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -69 +69 @@
             >>> vcv = CellVariable(mesh=m, rank=1)
             >>> vfv = FaceVariable(mesh=m, rank=1)
-            >>> ConvectionTerm(coeff = cv)
+            >>> __ConvectionTerm(coeff = cv)
             Traceback (most recent call last):
                 ...
             TypeError: The coefficient must be a vector value.
-            >>> ConvectionTerm(coeff = fv)
+            >>> __ConvectionTerm(coeff = fv)
             Traceback (most recent call last):
                 ...
             TypeError: The coefficient must be a vector value.
-            >>> ConvectionTerm(coeff = vcv)
-            ConvectionTerm(coeff=_ArithmeticCellToFaceVariable(value=array([[ 0.,  0.,  0.]]), mesh=UniformGrid1D(dx=1.0, nx=2)))
-            >>> ConvectionTerm(coeff = vfv)
-            ConvectionTerm(coeff=FaceVariable(value=array([[ 0.,  0.,  0.]]), mesh=UniformGrid1D(dx=1.0, nx=2)))
-            >>> ConvectionTerm(coeff = (1,))
-            ConvectionTerm(coeff=(1,))
+            >>> __ConvectionTerm(coeff = vcv)
+            __ConvectionTerm(coeff=_ArithmeticCellToFaceVariable(value=array([[ 0.,  0.,  0.]]), mesh=UniformGrid1D(dx=1.0, nx=2)))
+            >>> __ConvectionTerm(coeff = vfv)
+            __ConvectionTerm(coeff=FaceVariable(value=array([[ 0.,  0.,  0.]]), mesh=UniformGrid1D(dx=1.0, nx=2)))
+            >>> __ConvectionTerm(coeff = (1,))
+            __ConvectionTerm(coeff=(1,))
             >>> from fipy.terms.explicitUpwindConvectionTerm import ExplicitUpwindConvectionTerm
             >>> ExplicitUpwindConvectionTerm(coeff = (0,)).solve(var = cv)
@@ -94 +94 @@
             >>> vcv2 = CellVariable(mesh=m2, rank=1)
             >>> vfv2 = FaceVariable(mesh=m2, rank=1)
-            >>> ConvectionTerm(coeff=vcv2)
-            ConvectionTerm(coeff=_ArithmeticCellToFaceVariable(value=array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.],
+            >>> __ConvectionTerm(coeff=vcv2)
+            __ConvectionTerm(coeff=_ArithmeticCellToFaceVariable(value=array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.],
                    [ 0.,  0.,  0.,  0.,  0.,  0.,  0.]]), mesh=UniformGrid2D(dx=1.0, dy=1.0, nx=2, ny=1)))
-            >>> ConvectionTerm(coeff=vfv2)
-            ConvectionTerm(coeff=FaceVariable(value=array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.],
+            >>> __ConvectionTerm(coeff=vfv2)
+            __ConvectionTerm(coeff=FaceVariable(value=array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.],
                    [ 0.,  0.,  0.,  0.,  0.,  0.,  0.]]), mesh=UniformGrid2D(dx=1.0, dy=1.0, nx=2, ny=1)))
             >>> ExplicitUpwindConvectionTerm(coeff = ((0,),(0,))).solve(var=cv2)
@@ -108 +108 @@
           - `diffusionTerm` : ** deprecated **. The Peclet number is calculated automatically.
         """
+        if self.__class__ is ConvectionTerm:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         if diffusionTerm is not None:
             import warnings
@@ -173 +176 @@
             return FaceTerm.__add__(self, other)
 
+class __ConvectionTerm(ConvectionTerm): 
+    """
+    Dummy subclass for tests
+    """
+    pass 
+
 def _test(): 
     import doctest

trunk/fipy/terms/equation.py

@@ -7 +7 @@
  #  FILE: "equation.py"
  #                                    created: 11/9/04 {11:51:08 AM} 
- #                                last update: 7/25/07 {9:57:05 AM} 
+ #                                last update: 10/23/08 {4:10:02 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -134 +134 @@
         Add a `Term` to another `Term`, number or variable.
 
-           >>> Term(coeff=1.) + 10. + Term(2.)
-           10.0 + Term(coeff=3.0) == 0
-           >>> Term(coeff=1.) + Term(coeff=2.) + Term(coeff=3.)
-           Term(coeff=6.0)
+           >>> __Term(coeff=1.) + 10. + __Term(2.)
+           10.0 + __Term(coeff=3.0) == 0
+           >>> __Term(coeff=1.) + __Term(coeff=2.) + __Term(coeff=3.)
+           __Term(coeff=6.0)
 
         """
@@ -178 +178 @@
          Negate a `Term`.
 
-           >>> -(Term(coeff=1.) - Term(coeff=2.))
-           Term(coeff=1.0)
+           >>> -(__Term(coeff=1.) - __Term(coeff=2.))
+           __Term(coeff=1.0)
 
         """
@@ -189 +189 @@
                 
         return dup
+
+class __Term(Term):
+    """
+    Dummy subclass for tests
+    """
+    pass 
 
 def _test(): 

trunk/fipy/terms/faceTerm.py

@@ -7 +7 @@
  #  FILE: "faceTerm.py"
  #                                    created: 11/17/03 {10:29:10 AM} 
- #                                last update: 6/7/08 {11:11:20 PM} 
+ #                                last update: 10/23/08 {3:13:50 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -55 +55 @@
     """
     def __init__(self, coeff=1.):
+        if self.__class__ is FaceTerm:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         Term.__init__(self, coeff=coeff)
         self.coeffMatrix = None

trunk/fipy/terms/sourceTerm.py

@@ -7 +7 @@
  #  FILE: "sourceTerm.py"
  #                                    created: 11/28/03 {11:36:25 AM} 
- #                                last update: 3/28/07 {10:17:48 AM} 
+ #                                last update: 10/23/08 {3:14:26 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -50 +50 @@
     """
     def __init__(self, coeff = 0.):
+        if self.__class__ is SourceTerm:
+            raise NotImplementedError, "can't instantiate abstract base class"
         CellTerm.__init__(self, coeff = coeff) 
         

trunk/fipy/terms/term.py

@@ -7 +7 @@
  #  FILE: "term.py"
  #                                    created: 11/12/03 {10:54:37 AM} 
- #                                last update: 9/17/08 {9:34:46 AM} 
+ #                                last update: 10/23/08 {4:05:43 PM} 
  #  Author: Jonathan Guyer <guyer@nist.gov>
  #  Author: Daniel Wheeler <daniel.wheeler@nist.gov>
@@ -64 +64 @@
 
         """  
+        if self.__class__ is Term:
+            raise NotImplementedError, "can't instantiate abstract base class"
+            
         self.coeff = coeff
         self.geomCoeff = None
@@ -73 +76 @@
         
     def _buildMatrix(self, var, SparseMatrix, boundaryConditions, dt, equation=None):