SLIP                     Library "JINRLIB"                       
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         PROGRAMS OF THE SOLUTION OF THE STURM-LIOUVILLE PROBLEM     
                                                                     visitor here.
    SLIP1  - Program of the numerical solution of the Sturm-Liouville
             problem basing on the continuous analog of the Newton method;
    SLIPS2 - program for numerical solution of the Sturm-Liouville problem
             for the system of differential equations;
    SLIPH4 - program for numerical solution of the Sturm-Liouville problem.


    SLIP1 - PROGRAM OF THE NUMERICAL SOLUTION OF THE STURM-LIOUVILLE PROBLEM 
            BASING ON THE CONTINUOUS ANALOG OF THE NEWTON METHOD

    Authors: I.V.Puzynin, T.P.Puzynina
    Language: Fortran

    The algorithm of the numerical solution of the Sturm-Liouville
    problem was described basing on the continuous analog of the
    Newton method. The program was described realizing this
    algorithm on FORTRAN too.
    Sources and the detailed description (in Russian, format .ps) are submitted. 


    SLIPS2 - PROGRAM FOR NUMERICAL SOLUTION OF THE STURM-LIOUVILLE PROBLEM
               FOR THE SYSTEM OF DIFFERENTIAL EQUATIONS

    Author: T.P.Puzynina
    Language: Fortran

    A program complex SLIPS2 is intended for solving a partial Sturm-Liouville
    problem for a system of two 2-nd order differential equations with
    predetermined boundary conditions.
    The software realizes modified iteration schemes of the continuous analogue
    of Newton's method with selection of an iteration parameter.
    Among them there is a scheme with a fixed eigenvalue shift and 
    orthogonalization  of the eigenfunction vector at each iteration. 
    The program was used for calculation of energy levels and wave functions
    of mesomolecules and a scattering problem in a two-level approximation of
    an adiabatic representation of a three-body problem with Coulomb interation
    as well as for the inverse scattering problem in the framework of Bargmann
    formalism and for a number of other problems.
    The program can be effectively used on its own and as a generator of initial
    approximations at numerical analysis of convergence of various multi-level
    approximations for quantum mechanics systems.
    The text of the program is written in the Fortran language and an example
    of its use is presented.
    Sources and the detailed description (in Russian, format .ps) are submitted.


    SLIPH4 - PROGRAM FOR NUMERICAL SOLUTION OF THE STURM-LIOUVILLE PROBLEM 

    Authors: I.V.Puzynin, T.P.Puzynina, T.A.Strizh
    Language: Fortran

    SLIPH4 program complex for the numerical solution of the Sturm-
    Liouville problem for the second-order homogeneous linear differential
    equation with homogeneous boundary conditions is described.
    The continuous analogue of the Newton method is used. The descrete
    scheme that has been realized in the approach provides an accuracy
    of the order of four with respect to the mesh step of the independent
    variable. The program for the initial approximation to the solution 
    calculations with the help of a modified Newton method for the
    polynomial roots finding with the calculated root elimination is
    added to the complex. The possibility of using the modified method
    with eigenvalue fixing and obtained approximate eigenfunction 
    additional orthogonalizaton is realized in complex. This permits to
    solve both the initial approximation problem and its more precise
    definition by the same scheme.The program write-up is presented.
    Examples illustrating the program complex using are given.
    The investigation has been performed at the Laboratory of  Computing
    Techniques and Automation, JINR.
    Sources and the detailed description (in Russian, format .ps) are submitted.