Simplify multiple isinstance calls.

theano/sparse/basic.py

@@ -38,7 +38,7 @@ def _is_sparse_variable(x):
     @rtype: boolean
     @return: True iff x is a L{SparseVariable} (and not a L{tensor.TensorType})
     """
-    if not isinstance(x.type, SparseType) and not isinstance(x.type, tensor.TensorType):
+    if not isinstance(x.type, (SparseType, tensor.TensorType)):
         raise NotImplementedError("this function should only be called on *variables* (of type sparse.SparseType or tensor.TensorType), not,", x)
     return isinstance(x.type, SparseType)
 def _is_dense_variable(x):
@@ -46,7 +46,7 @@ def _is_dense_variable(x):
     @rtype: boolean
     @return: True unless x is a L{SparseVariable} (and not a L{tensor.TensorType})
     """
-    if not isinstance(x.type, SparseType) and not isinstance(x.type, tensor.TensorType):
+    if not isinstance(x.type, (SparseType, tensor.TensorType)):
         raise NotImplementedError("this function should only be called on *variables* (of type sparse.SparseType or tensor.TensorType), not,", x)
     return isinstance(x.type, tensor.TensorType)
 
@@ -55,7 +55,7 @@ def _is_sparse(x):
     @rtype: boolean
     @return: True iff x is a L{scipy.sparse.spmatrix} (and not a L{numpy.ndarray})
     """
-    if not isinstance(x, scipy.sparse.spmatrix) and not isinstance(x, numpy.ndarray):
+    if not isinstance(x, (scipy.sparse.spmatrix, numpy.ndarray)):
         raise NotImplementedError("this function should only be called on sparse.scipy.sparse.spmatrix or numpy.ndarray, not,", x)
     return isinstance(x, scipy.sparse.spmatrix)
 def _is_dense(x):
@@ -63,7 +63,7 @@ def _is_dense(x):
     @rtype: boolean
     @return: True unless x is a L{scipy.sparse.spmatrix} (and not a L{numpy.ndarray})
     """
-    if not isinstance(x, scipy.sparse.spmatrix) and not isinstance(x, numpy.ndarray):
+    if not isinstance(x, (scipy.sparse.spmatrix, numpy.ndarray)):
         raise NotImplementedError("this function should only be called on sparse.scipy.sparse.spmatrix or numpy.ndarray, not,", x)
     return isinstance(x, numpy.ndarray)