Return the Strakoš matrix.

    See [Str92]_.

def strakos(n, l_min=0.1, l_max=100, rho=0.9):
    """Return the Strakoš matrix.

    See [Str92]_.
    """
    d = [l_min + (i-1)*1./(n-1)*(l_max-l_min)*(rho**(n-i))
         for i in range(1, n+1)]
    return numpy.diag(d)