From e6dca29a97830bb0fa9c35c2bfedd99336e1d636 Mon Sep 17 00:00:00 2001
From: Oliver Sander <sander@igpm.rwth-aachen.de>
Date: Mon, 24 Mar 2014 15:51:32 +0000
Subject: [PATCH] Use a better initial iterate for the TargetSpaceTRSolver than
coefficients_[0]
The new initial iterate is constructed by interpolating the values in Euclidean
space, and projecting back onto TargetSpace. This has two advantages:
1) It's a better initial iterate, so we should converge faster than starting
from coefficients_[0]
2) It makes it easier for ADOL-C to pick up correct second derivatives.
Hence we are able to reduce the minimum number of iterations of the
target space tr solver.
[[Imported from SVN: r9683]]
---
dune/gfe/localgeodesicfefunction.hh | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/dune/gfe/localgeodesicfefunction.hh b/dune/gfe/localgeodesicfefunction.hh
index 9eadf45e..9316ff48 100644
--- a/dune/gfe/localgeodesicfefunction.hh
+++ b/dune/gfe/localgeodesicfefunction.hh
@@ -9,6 +9,7 @@
#include <dune/gfe/averagedistanceassembler.hh>
#include <dune/gfe/targetspacertrsolver.hh>
+#include <dune/gfe/localprojectedfefunction.hh>
#include <dune/gfe/rigidbodymotion.hh>
#include <dune/gfe/tensor3.hh>
@@ -187,10 +188,15 @@ evaluate(const Dune::FieldVector<ctype, dim>& local) const
// The energy functional whose mimimizer is the value of the geodesic interpolation
AverageDistanceAssembler<TargetSpace> assembler(coefficients_, w);
+ // Create a reasonable initial iterate for the iterative solver
+ Dune::GFE::LocalProjectedFEFunction<dim,ctype,LocalFiniteElement,TargetSpace> localProjectedFEFunction(localFiniteElement_, coefficients_);
+ TargetSpace initialIterate = localProjectedFEFunction.evaluate(local);
+
+ // Iteratively solve the GFE minimization problem
TargetSpaceRiemannianTRSolver<TargetSpace> solver;
solver.setup(&assembler,
- coefficients_[0], // initial iterate
+ initialIterate,
1e-14, // tolerance
100, // maxTrustRegionSteps
2, // initial trust region radius
--
GitLab