Laboratoire de l'Informatique et du Parallélisme » Pobyso

def smo_is_diagonal_complete_matrix(mat):

    """

    Check that all the element on the diagonal are not 0.

    """

    dimensions = mat.dimensions()

    # Must be a bidimensional matrix.

    if len(dimensions) != 2:

        return False

    # Must be square.

    if dimensions[0] != dimensions[1]:

        return False

    # A 1x1 matrix is diagonal complete if it's single element is not 0.

    if dimensions[0] == 1:

        if mat[0, 0] != 0:

            return True

        else:

            return False

    # End if

    for rowIndex in xrange(0, dimensions[0]):

        if mat[rowIndex, rowIndex] == 0:

            print mat.rows()[rowIndex], rowIndex

            return False

    return True

# End smo_is_diagonal_complete_matrix

def smo_is_lower_triangular_matrix(mat):

    """

    Check that the matrix is lower triangular.

    """

    dimensions = mat.dimensions()

    # Must be a bidimensional matrix.

    if len(dimensions) != 2:

        return False

    # Must be square.

    if dimensions[0] != dimensions[1]:

        return False

    # A 1x1 matrix is lower triangular.

    if dimensions[0] == 1:

        return True

    for rowIndex in xrange(0, dimensions[0]):

        for colIndex in xrange(rowIndex + 1, dimensions[1]):

            if mat[rowIndex, colIndex] != 0:

                print mat.rows()[rowIndex]

                return False

    return True

# End smo_is_lower_triangular_matrix