def __init__(self, A):
    if (not self._cholesky):
        raise nx.NetworkXError('Cholesky solver unavailable.')
    self._chol = self._cholesky(A)
def __init__(self, A):
    if (not self._cholesky):
        raise nx.NetworkXError('Cholesky solver unavailable.')
    self._chol = self._cholesky(A)