From d6236d3b26f6b652c452d884c440099892fdcdba Mon Sep 17 00:00:00 2001 From: Gael Guennebaud Date: Wed, 10 Sep 2014 11:54:20 +0200 Subject: [PATCH] Fix bug #791: infinite loop in JacobiSVD in the presence of NaN. --- Eigen/src/SVD/JacobiSVD.h | 3 ++- test/jacobisvd.cpp | 16 ++++++++++++---- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/Eigen/src/SVD/JacobiSVD.h b/Eigen/src/SVD/JacobiSVD.h index 6f3907f5d..6ff689de3 100644 --- a/Eigen/src/SVD/JacobiSVD.h +++ b/Eigen/src/SVD/JacobiSVD.h @@ -741,7 +741,8 @@ JacobiSVD::compute(const MatrixType& matrix, unsig EIGEN_USING_STD_MATH(max); RealScalar threshold = (max)(considerAsZero, precision * (max)(abs(m_workMatrix.coeff(p,p)), abs(m_workMatrix.coeff(q,q)))); - if((max)(abs(m_workMatrix.coeff(p,q)),abs(m_workMatrix.coeff(q,p))) > threshold) + // We compare both values to threshold instead of calling max to be robust to NaN (See bug 791) + if(abs(m_workMatrix.coeff(p,q))>threshold || abs(m_workMatrix.coeff(q,p)) > threshold) { finished = false; diff --git a/test/jacobisvd.cpp b/test/jacobisvd.cpp index 36721b496..422d46695 100644 --- a/test/jacobisvd.cpp +++ b/test/jacobisvd.cpp @@ -315,16 +315,23 @@ void jacobisvd_inf_nan() VERIFY(sub(some_inf, some_inf) != sub(some_inf, some_inf)); svd.compute(MatrixType::Constant(10,10,some_inf), ComputeFullU | ComputeFullV); - Scalar some_nan = zero() / zero(); - VERIFY(some_nan != some_nan); - svd.compute(MatrixType::Constant(10,10,some_nan), ComputeFullU | ComputeFullV); + Scalar nan = std::numeric_limits::quiet_NaN(); + VERIFY(nan != nan); + svd.compute(MatrixType::Constant(10,10,nan), ComputeFullU | ComputeFullV); MatrixType m = MatrixType::Zero(10,10); m(internal::random(0,9), internal::random(0,9)) = some_inf; svd.compute(m, ComputeFullU | ComputeFullV); m = MatrixType::Zero(10,10); - m(internal::random(0,9), internal::random(0,9)) = some_nan; + m(internal::random(0,9), internal::random(0,9)) = nan; + svd.compute(m, ComputeFullU | ComputeFullV); + + // regression test for bug 791 + m.resize(3,3); + m << 0, 2*NumTraits::epsilon(), 0.5, + 0, -0.5, 0, + nan, 0, 0; svd.compute(m, ComputeFullU | ComputeFullV); } @@ -437,6 +444,7 @@ void test_jacobisvd() // Test on inf/nan matrix CALL_SUBTEST_7( jacobisvd_inf_nan() ); + CALL_SUBTEST_10( jacobisvd_inf_nan() ); } CALL_SUBTEST_7(( jacobisvd(MatrixXf(internal::random(EIGEN_TEST_MAX_SIZE/4, EIGEN_TEST_MAX_SIZE/2), internal::random(EIGEN_TEST_MAX_SIZE/4, EIGEN_TEST_MAX_SIZE/2))) ));