From a6cb8d1abb4c72e02313de8022d75c85a8bcf2be Mon Sep 17 00:00:00 2001 From: Alexandru Fikl <alexfikl@gmail.com> Date: Tue, 25 Aug 2020 20:13:53 -0500 Subject: [PATCH] add some docs --- grudge/symbolic/primitives.py | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/grudge/symbolic/primitives.py b/grudge/symbolic/primitives.py index d06ae9f3..d706314c 100644 --- a/grudge/symbolic/primitives.py +++ b/grudge/symbolic/primitives.py @@ -503,11 +503,24 @@ def mv_nodes(ambient_dim, dd=None): def forward_metric_nth_derivative(xyz_axis, ref_axes, dd=None): r""" - Pointwise metric derivatives representing + Pointwise metric derivatives representing repeated derivatives .. math:: - \frac{\partial x_{\mathrm{xyz\_axis}} }{\partial r_{\mathrm{rst\_axis}} } + \frac{\partial^n x_{\mathrm{xyz\_axis}} }{\partial r_{\mathrm{ref\_axes}}} + + where *ref_axes* is a multi-index description. + + :arg ref_axes: a :class:`tuple` of tuples indicating indices of + coordinate axes of the reference element to the number of derivatives + which will be taken. For example, the value ``((0, 2), (1, 1))`` + indicates taking the second derivative with respect to the first + axis and the first derivative with respect to the second + axis. Each axis must occur only once and the tuple must be sorted + by the axis index. + + May also be a singile integer *i*, which is viewed as equivalent + to ``((i, 1),)``. """ if isinstance(ref_axes, int): @@ -546,6 +559,14 @@ def forward_metric_nth_derivative(xyz_axis, ref_axes, dd=None): def forward_metric_derivative(xyz_axis, rst_axis, dd=None): + r""" + Pointwise metric derivatives representing + + .. math:: + + \frac{\partial x_{\mathrm{xyz\_axis}} }{\partial r_{\mathrm{rst\_axis}}} + """ + return forward_metric_nth_derivative(xyz_axis, rst_axis, dd=dd) @@ -800,6 +821,8 @@ def normal(dd, ambient_dim, dim=None): def summed_curvature(ambient_dim, dim=None, dd=None): + """Sum of the principal curvatures""" + if dim is None: dim = ambient_dim - 1 @@ -814,6 +837,7 @@ def summed_curvature(ambient_dim, dim=None, dd=None): def mean_curvature(ambient_dim, dim=None, dd=None): + """Averaged (by dimension) sum of the principal curvatures.""" return 1.0 / (ambient_dim-1.0) * summed_curvature(ambient_dim, dim=dim, dd=dd) # }}} -- GitLab