 EVSL  1.1.0 EigenValues Slicing Library
ratlanNr.c File Reference

Rational Filtered no-restart Lanczos. More...

`#include <stdlib.h>`
`#include <stdio.h>`
`#include <math.h>`
`#include <string.h>`
`#include <float.h>`
`#include <complex.h>`
`#include "def.h"`
`#include "blaslapack.h"`
`#include "struct.h"`
`#include "internal_proto.h"`

Go to the source code of this file.

## Macros

#define FILTER_VINIT   1

## Functions

int RatLanNr (double *intv, int maxit, double tol, double *vinit, ratparams *rat, int *nevOut, double **lamo, double **Wo, double **reso, FILE *fstats)
Rational filtering Lanczos process [NON-restarted version]. More...

## Detailed Description

Rational Filtered no-restart Lanczos.

Definition in file ratlanNr.c.

## Macro Definition Documentation

 #define FILTER_VINIT   1

if filter the initial vector

Definition at line 18 of file ratlanNr.c.

## Function Documentation

 int RatLanNr ( double * intv, int maxit, double tol, double * vinit, ratparams * rat, int * nevOut, double ** lamo, double ** Wo, double ** reso, FILE * fstats )

Rational filtering Lanczos process [NON-restarted version].

Parameters
 intv an array of length 4 [intv, intv] is the interval of desired eigenvalues [intv, intv] is the global interval of all eigenvalues it must contain all eigenvalues of A maxit max Num of outer Lanczos steps allowed –[max dim of Krylov subspace] tol tolerance for convergence. The code uses a stopping criterion based on the convergence of the restricted trace. i.e., the sum of the eigenvalues of T_k that are in the desired interval. This test is rather simple since these eigenvalues are above `bar'. We want the relative error on this restricted trace to be less than tol. Note that the test performed on filtered matrix only - but the actual residual norm associated with the original matrix A is returned vinit initial vector for Lanczos – [optional]
Warning
RatLanNr() Modifies the following variables:
Parameters
 [out] rat A struct containing the rational filter [out] nevOut Number of eigenvalues/vectors computed [out] Wo A set of eigenvectors [n x nevOut matrix] [out] lamo Associated eigenvalues [nevOut x 1 vector] [out] reso Associated residual norms [nev x 1 vector] [out] fstats File stream which stats are printed to

Definition at line 54 of file ratlanNr.c.

Referenced by evsl_ratlannr(), and main().

Here is the call graph for this function: Here is the caller graph for this function: 