From 856f6a5284b4de79fea6baeedaa2738f8bd1368a Mon Sep 17 00:00:00 2001 From: kronbichler Date: Fri, 7 Dec 2012 09:07:10 +0000 Subject: [PATCH] Improve comments. Improve check for over-/underflow in l2_norm slightly. git-svn-id: https://svn.dealii.org/trunk@27776 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/include/deal.II/lac/vector.templates.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/deal.II/include/deal.II/lac/vector.templates.h b/deal.II/include/deal.II/lac/vector.templates.h index 60fb6cac10..e7f981240d 100644 --- a/deal.II/include/deal.II/lac/vector.templates.h +++ b/deal.II/include/deal.II/lac/vector.templates.h @@ -553,7 +553,7 @@ namespace internal // worst case error made by this algorithm is on the order O(eps * // log2(vec_size)), whereas a naive summation is O(eps * vec_size). Even // though the Kahan summation is even more accurate with an error O(eps) - // by carrying along remainders not captured by the sum, that involves + // by carrying along remainders not captured by the main sum, that involves // additional costs which are not worthwhile. See the Wikipedia article on // the Kahan summation algorithm. @@ -561,7 +561,7 @@ namespace internal // easily parallelized without changing the order of how the elements are // added (floating point addition is not associative). For the same vector // size and minimum_parallel_grainsize, the blocks are always the - // same. Only at the innermost level, eight values are summed up + // same and added pairwise. At the innermost level, eight values are added // consecutively in order to better balance multiplications and additions. // The code returns the result as the last argument in order to make @@ -790,7 +790,7 @@ Vector::l2_norm () const internal::Vector::accumulate (internal::Vector::Norm2(), val, val, real_type(), vec_size, norm_square); if (numbers::is_finite(norm_square) && - norm_square > std::numeric_limits::min()) + norm_square >= std::numeric_limits::min()) return std::sqrt(norm_square); else { @@ -833,7 +833,7 @@ Vector::lp_norm (const real_type p) const internal::Vector::accumulate (internal::Vector::NormP(), val, val, p, vec_size, sum); - if (numbers::is_finite(sum) && sum > std::numeric_limits::min()) + if (numbers::is_finite(sum) && sum >= std::numeric_limits::min()) return std::pow(sum, static_cast(1./p)); else { -- 2.39.5