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authorjthorn <jthorn@f88db872-0e4f-0410-b76b-b9085cfa78c5>2005-05-11 12:00:30 +0000
committerjthorn <jthorn@f88db872-0e4f-0410-b76b-b9085cfa78c5>2005-05-11 12:00:30 +0000
commit132ef4236ecbfe0539ad46d48450f70846635c6f (patch)
treef55c99d4e089d71b654820ff17a72b041817bd79 /doc
parente0904c944cfa784ca76dfc222072668defef921d (diff)
standardize terminology: $\Theta$ = expansion of trial surface
(a long time ago I used $H$, and I missed a few places when I switched) git-svn-id: http://svn.einsteintoolkit.org/cactus/EinsteinAnalysis/AHFinderDirect/trunk@1408 f88db872-0e4f-0410-b76b-b9085cfa78c5
Diffstat (limited to 'doc')
-rw-r--r--doc/documentation.tex18
1 files changed, 9 insertions, 9 deletions
diff --git a/doc/documentation.tex b/doc/documentation.tex
index 9bace6c..5c6551f 100644
--- a/doc/documentation.tex
+++ b/doc/documentation.tex
@@ -153,7 +153,7 @@ There may be several such surfaces, some nested inside others; an
In terms of the usual $3+1$ variables, an apparent horizon satisfies
the equation
\begin{equation}
-H \equiv \del_i n^i + K_\ij n^i n^j - K = 0
+\Theta \equiv \del_i n^i + K_\ij n^i n^j - K = 0
\label{AHFinderDirect/eqn-horizon}
\end{equation}
where $n^i$ is the outward-pointing unit normal to the apparent horizon,
@@ -446,8 +446,8 @@ section~\ref{AHFinderDirect/sect-examples} should make this clear.
\item[\code{"algorithm highlights"}]
\mbox{}\\
Also print a single line for each Newton iteration giving
- the 2-norm and $\infty$-norm of the $H(h)$ function defined
- by equation~\eqref{AHFinderDirect/eqn-horizon}.
+ the 2-norm and $\infty$-norm of the $\Theta(h)$ function
+ defined by equation~\eqref{AHFinderDirect/eqn-horizon}.
This is the default.
\item[\code{"algorithm details"}]
\mbox{}\\
@@ -1639,7 +1639,7 @@ improved convergence).
Computationally, this algorithm has 3 main parts:
\begin{itemize}
-\item Computation of the ``horizon function'' $H(h)$ given a trial
+\item Computation of the ``horizon function'' $\Theta(h)$ given a trial
surface defined by a trial horizon shape function $h$. This is
done by interpolating the Cactus geometry fields $g_\ij$ and
$K_\ij$ (and optionally $\psi$) from the 3-D $xyz$ grid to the
@@ -1647,8 +1647,8 @@ Computationally, this algorithm has 3 main parts:
$\partial_k g_\ij$ in the interpolation process), then doing
all further computations with angular grid functions defined
solely on $S^2$ (\ie{} at the horizon-surface grid points).
-\item Computation of the Jacobian matrix $\Jac[H(h)]$ of $H(h)$. This
- thorn incorporates the \defn{symbolic differentiation} technique
+\item Computation of the Jacobian matrix $\Jac[\Theta(h)]$ of $\Theta(h)$.
+ This thorn incorporates the \defn{symbolic differentiation} technique
described in
\cite{AEIThorns/AHFinderDirect/Thornburg-1996-apparent-horizon-finding},
so this computation is quite fast. The Jacobian is a highly
@@ -1656,9 +1656,9 @@ Computationally, this algorithm has 3 main parts:
as either a dense matrix (for debugging purposes), or a sparse
matrix (the default). Which option is used is determined by
a compile-time configuration in \verb|src/include/config.h|.
-\item Solving the nonlinear equations $H(h) = 0$ by a global Newton's
- method or a variant. How this is done depends on how the Jacobian
- is stored. At present,
+\item Solving the nonlinear equations $\Theta(h) = 0$ by a global
+ Newton's method or a variant. How this is done depends on how
+ the Jacobian is stored. At present,
\begin{itemize}
\item If \thorn{AHFinderDirect} is configured to store the
Jacobian as a dense matrix, then LAPACK is used to solve