diff --git a/dune/tectonic/localfriction.hh b/dune/tectonic/localfriction.hh index 5edabfca11b22d25d913ef060f83a5021f56ac2f..2320302a47daf991724ad9bf8eba36554d2b5897 100644 --- a/dune/tectonic/localfriction.hh +++ b/dune/tectonic/localfriction.hh @@ -46,19 +46,19 @@ template <int dimension> class LocalFriction { /** Formula for the derivative: - \f{align*}{ + \f{align*}{ \frac {d^2}{dz^2} H(|z|) &= \frac d{dz} \left( H'(|z|) \otimes \frac z{|z|} \right)\\ &= H''(|z|) \frac z{|z|} \otimes \frac z{|z|} + H'(|z|) \left( \frac {|z| \operatorname{id} - z \otimes z/|z|}{|z|^2} - \right)\\ + \right)\\ &= \frac {H''(|z|)}{|z|^2} z \otimes z + \frac {H'(|z|)}{|z|} \operatorname{id} - \frac {H'(|z|)}{|z|^3} z \otimes z\\ &= \left( \frac {H''(|z|)}{|z|^2} - \frac {H'(|z|)}{|z|^3} \right) z - \otimes z + \otimes z + \frac {H'(|z|)}{|z|} \operatorname{id} - \f} + \f} */ void addHessian(VectorType const &x, MatrixType &A) const { double const xnorm2 = x.two_norm2();