Add method to zero matrix entries

Author: guyer

fipy/matrices/pysparseMatrix.py

@@ -392,6 +392,10 @@ def T(self):
 
         return _PysparseMatrix(matrix=A_T)
 
+    def zeroEntries(self):
+        _, irow, jcol = self.matrix.find()
+        self.put(0, irow, jcol)
+
 class _PysparseMatrixFromShape(_PysparseMatrix):
 
     def __init__(self, rows, cols,

fipy/matrices/scipyMatrix.py

@@ -379,6 +379,10 @@ def T(self):
         """
         return _ScipyMatrix(matrix=self.matrix.transpose(copy=True))
 
+    def zeroEntries(self):
+        id1, id2 = self.matrix.nonzero()
+        self.matrix[id1, id2] = 0
+
 class _ScipyMatrixFromShape(_ScipyMatrix):
 
     def __init__(self, rows, cols,

fipy/matrices/sparseMatrix.py

@@ -134,6 +134,11 @@ def LIL(self):
     def T(self):
         raise NotImplementedError
 
+    def zeroEntries(self):
+        """Insert zeros into nonzero matrix entries.
+        """
+        raise NotImplementedError
+
     def _matrix2mesh(self, ids):
         """Convert matrix row indices to mesh cell indices
         """

fipy/matrices/trilinosMatrix.py

@@ -715,6 +715,9 @@ def T(self):
 
         return _TrilinosMatrix(matrix=A_T_bis)
 
+    def zeroEntries(self):
+        self.matrix.PutScalar(0)
+
 class _TrilinosMatrixFromShape(_TrilinosMatrix):
     def __init__(self, rows, cols,
                  nonZerosPerRow=1, exactNonZeros=False, matrix=None):