Eigen::EigenvalueRange Struct Reference

#include <Eigen/src/Eigenvalues/TridiagonalBisection.h>

Detailed Description

Selects which eigenvalues to compute in a spectral-bisection solve.

This is defined in the Eigenvalues module.

#include <Eigen/Eigenvalues> 

Passed to TridiagonalEigenSolver::computeEigenvalues(). The Sturm-sequence bisection algorithm can compute an arbitrary contiguous subset of the spectrum, which the implicit-QR algorithm cannot. Three modes are provided:

• all(): every eigenvalue (the default),
• indices(il, iu): the eigenvalues with 0-based ascending indices in the half-open range [il, iu) (i.e. the (iu - il) smallest starting at il),
• values(vl, vu): the eigenvalues lying in the half-open interval [vl, vu) (lower-closed, upper-open, like indices(); an eigenvalue exactly equal to vl is selected, one equal to vu is not). Endpoint membership is resolved against the computed eigenvalue approximations, so an eigenvalue within roughly n*eps*||T|| of an endpoint – but not exactly on it – may resolve to either side of that endpoint.

In every mode the computed eigenvalues are returned in non-decreasing order.

Static Public Member Functions
static EigenvalueRange	all ()
static EigenvalueRange	indices (Index il, Index iu)
static EigenvalueRange	values (long double vl, long double vu)

Member Function Documentation

all()

static EigenvalueRange Eigen::EigenvalueRange::all ( )

inlinestatic

Returns

a selector for the entire spectrum.

indices()

static EigenvalueRange Eigen::EigenvalueRange::indices ( Index il, Index iu )

inlinestatic

Returns

a selector for the eigenvalues with 0-based indices in [il, iu).

values()

static EigenvalueRange Eigen::EigenvalueRange::values ( long double vl, long double vu )

inlinestatic

Returns

a selector for the eigenvalues in the half-open interval [vl, vu).

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The documentation for this struct was generated from the following file:

• /builds/libeigen/eigen/Eigen/src/Eigenvalues/TridiagonalBisection.h