From dd900f7f1fdcd72fc7ef3baf92fd6730c87fec8c Mon Sep 17 00:00:00 2001 From: Timo Heister Date: Sat, 11 Feb 2023 16:14:38 -0500 Subject: [PATCH] document MatrixFree mapping_update_flags --- include/deal.II/matrix_free/matrix_free.h | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/include/deal.II/matrix_free/matrix_free.h b/include/deal.II/matrix_free/matrix_free.h index 5e77a500fa..4f2d4750c1 100644 --- a/include/deal.II/matrix_free/matrix_free.h +++ b/include/deal.II/matrix_free/matrix_free.h @@ -352,15 +352,17 @@ public: unsigned int tasks_block_size; /** - * This flag determines the mapping data on cells that is cached. This - * class can cache data needed for gradient computations (inverse - * Jacobians), Jacobian determinants (JxW), quadrature points as well as - * data for Hessians (derivative of Jacobians). By default, only data for - * gradients and Jacobian determinants times quadrature weights, JxW, are - * cached. If quadrature points or second derivatives are needed, they - * must be specified by this field (even though second derivatives might - * still be evaluated on Cartesian cells without this option set here, - * since there the Jacobian describes the mapping completely). + * This flag determines what data needs to be computed and cached on cells. + * + * If your computations require operations like quadrature point locations + * or Hessians, these need to specified here (update_quadrature_points + * or update_hessians, respectively). Note that values, gradients, and + * Jacobian determinants (JxW values) are always computed regardless of the + * flags specified here. + * + * Note that some additional flags might be set automatically (for example + * second derivatives might be evaluated on Cartesian cells since there + * the Jacobian describes the mapping completely). */ UpdateFlags mapping_update_flags; @@ -500,7 +502,7 @@ public: * being a category) but can also be useful in other contexts where one * would like to control which cells together can form a batch of cells. * Such an example is "local time stepping", where cells of different - * caterogries progress with different time-step sizes and, as a + * categories progress with different time-step sizes and, as a * consequence, can only processed together with cells with the same * category. * -- 2.39.5