# Marco Marletta

# Programs for Solving Boundary-Eigenvalue Problems

## Waveguide (PDE) Problems

There is a
separate page on work with ** Michael Levitin ** on waveguide problems,
including MATLAB code. You will need MATLAB PDE Toolbox.

## Selfadjoint ODE Problems

(1) (by M.Marletta and L. Greenberg) The program SLEUTH for fourth order Sturm-Liouville problems. This program requires NAG software.

(2) (by M. Marletta) A version of SLEUTH which does not require NAG.

(3) (by M. Marletta) A driver for SLEUTH.

(4) Documentation for SLEUTH and for the eigenfunction routine.

(5) (by M. Marletta) A general-purpose code for problems in Hamiltonian form.

## Nonselfadjoint ODE Problems

(1) (by M. Marletta and L. Greenberg) The code
slnsagen.f is a package of subroutines
for calculating the ** eigenvalues ** in a rectangle,
a vertical strip, or a left half-plane.

(2) slnsagen.f must be linked to slnsa2.f for second order problems, to slnsa4.f for fourth order problems, and to slnsa6.f for sixth order problems. These routines require subroutines from the NAG library.

(3) (by ** Pierre Pinson **) There are also ** Fortran 90 ** routines for
computing ** eigenfunctions ** for problems of orders
two and four. These routines
require subroutines from the NAG library.
** With these routines you must replace ** slnsagen.f **
by slnsagen90.f **.

(4) Drivers for second, fourth and sixth order problems are slnsa2drive.f, slnsa4drive.f and slnsa6drive.f. These routines require subroutines from the NAG library.

(5)** A special code for all you guys in the US who don't have the NAG
library: an all-in-one package for second order problems only
to compute eigenvalues only! **

## Left-definite Right-indefinite Problems

(1) (By Marletta and Zettl) The code SLLDEF for left-definite right-indefinite Sturm-Liouville problems with coupled boundary conditions. Requires only LAPACK and a FORTRAN 77 compiler.

(2) A simple driver program
for the SLLDEF code.

## Coordinates:

- e-mail MarlettaM@cardiff.ac.uk
- t. (+44)(0)(29) 2087 5552
- f. (+44)(0)(29) 2087 4199
- s-mail Senghennydd Road, Cardiff CF24 4AG, United Kingdom