petsc_vector_test.C

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#include <libmesh/petsc_vector.h>
 
#ifdef LIBMESH_HAVE_PETSC
 
#include "numeric_vector_test.h"
 
 
using namespace libMesh;
 
class PetscVectorTest : public NumericVectorTest<PetscVector<Number>> {
public:
  CPPUNIT_TEST_SUITE( PetscVectorTest );
 
  NUMERICVECTORTEST
 
  CPPUNIT_TEST( testGetArray );
 
  CPPUNIT_TEST_SUITE_END();
 
  void testGetArray()
  {
    unsigned int min_block_size  = 2;
 
    // a different size on each processor.
    unsigned int my_p = my_comm->rank();
    unsigned int local_size  = (min_block_size + my_p);
    unsigned int global_size = 0;
    unsigned int my_offset = 0;
 
    for (libMesh::processor_id_type p=0; p<my_comm->size(); p++)
      {
        const unsigned int p_size =
          (min_block_size + static_cast<unsigned int>(p));
        global_size += p_size;
        if (p < my_p)
          my_offset += p_size;
      }
 
    PetscVector<Number> v(*my_comm, global_size, local_size);
 
    PetscScalar * values = v.get_array();
 
    for (unsigned int i=0; i<local_size; i++)
      values[i] = i;
 
    v.restore_array();
 
    v.close();
 
    // Check the values through the interface
    for (unsigned int i=0; i<local_size; i++)
      LIBMESH_ASSERT_FP_EQUAL(std::abs(v(my_offset + i)), i, TOLERANCE*TOLERANCE);
 
    // Check that we can see the same thing with get_array_read
    const PetscScalar * read_only_values = v.get_array_read();
 
    for (unsigned int i=0; i<local_size; i++)
      LIBMESH_ASSERT_FP_EQUAL(std::abs(read_only_values[i]), i, TOLERANCE*TOLERANCE);
 
    v.restore_array();
 
    // Test getting a read only array after getting a writable array
    values = v.get_array();
    read_only_values = v.get_array_read();
    CPPUNIT_ASSERT_EQUAL((intptr_t)read_only_values, (intptr_t)values);
 
    v.restore_array();
  }
 
};
 
CPPUNIT_TEST_SUITE_REGISTRATION( PetscVectorTest );
 
#endif // #ifdef LIBMESH_HAVE_PETSC