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authorGravatar Jitse Niesen <jitse@maths.leeds.ac.uk>2011-05-12 16:52:56 +0100
committerGravatar Jitse Niesen <jitse@maths.leeds.ac.uk>2011-05-12 16:52:56 +0100
commite22a52302103afd9366d10b0f71a52ffcf8fc235 (patch)
tree0583eff110589fe358706ecaab99ad0f3973914d /Eigen/src/Eigenvalues/ComplexSchur.h
parent0aa7425f1581b169f5d06a2818597331ad1de272 (diff)
Remove Eigen::internal::sqrt(), see bug #264.
Diffstat (limited to 'Eigen/src/Eigenvalues/ComplexSchur.h')
-rw-r--r--Eigen/src/Eigenvalues/ComplexSchur.h42
1 files changed, 1 insertions, 41 deletions
diff --git a/Eigen/src/Eigenvalues/ComplexSchur.h b/Eigen/src/Eigenvalues/ComplexSchur.h
index b1830f642..37bddd99f 100644
--- a/Eigen/src/Eigenvalues/ComplexSchur.h
+++ b/Eigen/src/Eigenvalues/ComplexSchur.h
@@ -227,46 +227,6 @@ template<typename _MatrixType> class ComplexSchur
friend struct internal::complex_schur_reduce_to_hessenberg<MatrixType, NumTraits<Scalar>::IsComplex>;
};
-namespace internal {
-
-/** Computes the principal value of the square root of the complex \a z. */
-template<typename RealScalar>
-std::complex<RealScalar> sqrt(const std::complex<RealScalar> &z)
-{
- RealScalar t, tre, tim;
-
- t = abs(z);
-
- if (abs(real(z)) <= abs(imag(z)))
- {
- // No cancellation in these formulas
- tre = sqrt(RealScalar(0.5)*(t + real(z)));
- tim = sqrt(RealScalar(0.5)*(t - real(z)));
- }
- else
- {
- // Stable computation of the above formulas
- if (z.real() > RealScalar(0))
- {
- tre = t + z.real();
- tim = abs(imag(z))*sqrt(RealScalar(0.5)/tre);
- tre = sqrt(RealScalar(0.5)*tre);
- }
- else
- {
- tim = t - z.real();
- tre = abs(imag(z))*sqrt(RealScalar(0.5)/tim);
- tim = sqrt(RealScalar(0.5)*tim);
- }
- }
- if(z.imag() < RealScalar(0))
- tim = -tim;
-
- return (std::complex<RealScalar>(tre,tim));
-}
-} // end namespace internal
-
-
/** If m_matT(i+1,i) is neglegible in floating point arithmetic
* compared to m_matT(i,i) and m_matT(j,j), then set it to zero and
* return true, else return false. */
@@ -302,7 +262,7 @@ typename ComplexSchur<MatrixType>::ComplexScalar ComplexSchur<MatrixType>::compu
ComplexScalar b = t.coeff(0,1) * t.coeff(1,0);
ComplexScalar c = t.coeff(0,0) - t.coeff(1,1);
- ComplexScalar disc = internal::sqrt(c*c + RealScalar(4)*b);
+ ComplexScalar disc = sqrt(c*c + RealScalar(4)*b);
ComplexScalar det = t.coeff(0,0) * t.coeff(1,1) - b;
ComplexScalar trace = t.coeff(0,0) + t.coeff(1,1);
ComplexScalar eival1 = (trace + disc) / RealScalar(2);