
                      Greetings from Universal Technical Systems 
                    ===============================================

        We are pleased to offer you a free copy of the essential part of our
        new product, TK Solver Plus.  For terms under which this offer is
        made, please see the README.TXT file.

        This introduction addresses four issues: 

           What is TK Solver and what is in this package?
           How to start using this package
           What more is available in TK Solver Plus?
           How to get more information and how to order more software


        W h a t   i s   T K   S o l v e r ?
        -----------------------------------

        TK Solver Plus is our latest addition to the line of personal
        computer software products started with Software Arts's TK!Solver
        four years ago. The original TK!Solver won wide acclaim among
        engineers, scientists, financial analysts, teachers and students for
        cutting short the problem-solving process. TK users have realized 
        time savings by a factor of 10 to 100, thanks to the fact that TK
        accepts equations or mathematical models in their natural form and
        generates their solutions regardless of the selection of known
        variables, the order of equations, or the location of unknowns on the
        left or right side of the equal sign.

        TK Plus goes far beyond the original TK. It provides the user with a
        comprehensive, open-ended and friendly problem-solving environment.
        This free PrevieWare edition of TK Solver (called FREETK) includes
        its most unique and powerful parts, the Direct and Iterative Solvers.
        It will give you a taste of declarative or rule-based programming as
        applied to numerical computations and logical relationships.

        While FREETK presents only a part of TK Plus capabilities, it is much
        more than an ordinary demo. It will let you solve countless practical
        problems within minutes of putting your hands on it.  For instance,
        it will let you analyze many aspects of loan management after
        entering a single formula:

                     payment = loan * rate / (1 - (1+rate)^-term)

        You will be able to describe what's going on in a DC circuit, and
        solve for any unknown components after entering 

                      R = R1 + R2 + R3 + ...  for a serial connection,

              1/R = 1/R1 + 1/R2 + 1/R3 + ...  for a parallel connection,

        and Ohm's or Kirchhoff's laws in their general form.  For AC
        calculations FREETK handles complex variables in orthogonal and polar
        or exponential notation.  Have you ever before heard of just typing
        (z,jz) = (x,jx) * (y,jy) and getting solutions for any combination of
        two unknowns and four knowns?


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        Mathematically speaking, TK will solve any equation or set of
        equations, linear or nonlinear.  Computationally speaking, you will
        be using a higher than "high level" language.  You will let the
        computer find its way through the maze of mathematical and logical
        relationships and, in fact, automatically generate a program each
        time you use a TK model for solving a particular problem.  And there
        is another dimension to TK:  It has achieved a proven record as a
        shell for developing knowledge bases (consisting of formulas,
        mathematical models, empirical data, etc.) and problem solving tools.


        How to get started with FREETK 
        ------------------------------

        FREETK runs on IBM PC/XT/AT or compatible computers with minimum 192K
        RAM and one floppy disk drive, although we suggest that you copy it
        to and run it from a hard disk, if available.  FREETK doesn't 
        require, but takes advantage of math co-processor if one is
        installed.

        Look at the the sample configuration file EXAMPLE.CFG.  You may not
        need any configuration file if you are satisfied with the default
        settings indicated as "Yes".  You may use your favorite text editor
        to change any "Yes" to "No" as desired, then rename EXAMPLE.CFG to
        FREETK.CFG and have it available when you load the FREETK program.

        Make sure that the FREETK.HLP and, if needed, FREETK.CFG files are
        available from current directory.

        The best bet for TK novices is to follow a hard copy of TUTORIAL.TXT.
        If you are serious about exploring the TK world you also should make
        and keep handy a hard copy of REFCARD.TXT, the file containing an
        abridged reference card from TK Solver Plus.

        The TK command structure is fairly simple, considering the power and
        versatility of the program. The most frequently used top level
        commands are displayed at the bottom of the screen (you can have this
        prompt removed by changing an appropriate setting in the CFG file to
        "No"). 

        The so-called slash commands beginning with  /  and sheet selection
        command beginning with  =  are supported by option menus.  To move
        around the TK sheets you can use the standard arrow and special keys
        in an intuitive fashion.

        FREETK comes with a context-sensitive help in the file FREETK.HLP,
        which is a subset of the Help file from full TKSolver Plus with a few
        tutorial additions.  You should be able to learn from the Help
        everything you need to start operating FREETK  --  just invoke it by
        pressing F1, go to the Help Index, look at and read the major topics
        at the beginning, and browse through the rest.  Help is there to
        serve you at any time you need it.  If it is invoked while a TK
        session is in progress, it will bring up information relevant to the
        current position of the cursor, the current error condition, or
        available command options.


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        Operating FREETK and taking full advantage of the TK concept take
        some amount of know-how and getting-used-to.  Here are a few hints:  

        Everything between TK and the user happens in so-called information
        sheets which are displayed in one or two windows on the screen. The
        most important ones are the RULE SHEET used for entering and
        displaying the rules or equations, and the VARIABLE SHEET where TK
        displays the variables with their input values (entered by the user)
        and output values or results (generated by TK).  You will quickly get
        used to this multi-sheet interface, and will appreciate the fact
        that certain kinds of information may always be found at certain
        places, managed in a consistent and uniform way.

        There are two keys on your keyboard that will help you a lot.
        Pressing the function key F2 terminates any command sequence or text
        entry in a field, restoring the original contents of the field.  When
        the cursor is in a Status Field in the Rule Sheet, pressing  C  works
        as a toggle switch bringing a particular rule into and out of
        operation -- handy when developing a model and sorting out which
        rules affect what.

        This leads to another point to keep in mind and take advantage of: in
        TK the solution of a model is not a one-way street.  It propagates
        through the maze of rules, equations and constraints in any
        conceivable way.  TK excels at inversion or turning the expressions
        inside out when evaluating a particular variable.  You may want to
        help it by, say, writing  1/(1+1/a)  instead of  a/(1+a)  or writing
        sin(2*phi)/2  instead of  sin(phi)*cos(phi).


        What more is available in TK Solver Plus ?
        -------------------------------------------

        By allowing the unbounded use of the Direct and Iterative solvers
        with up to 16 lines on the Rule Sheet and 32 lines on each of the
        Variable and Unit Sheets, FREETK has a considerable amount of power
        in its own right.  Nonetheless, FREETK provides only a glimpse of the
        full power of TK Solver Plus.  Aside from having no restrictions on
        the number of lines in any sheet (except those imposed by the amount
        of available memory), TK Solver Plus has many features beyond those
        available in FREETK.

        TK Solver Plus will help you with solving most (if not all) of your
        computational/mathematical problems by blending the solvers with more
        common concepts such as:  arrays of data or lists; high resolution
        graphics; spreadsheet-like tabular interface; and procedural
        programming.  The result is an integrated problem-solving environment
        with tools for solving differential equations, nonlinear curve
        fitting, arbitrary length integer arithmetic, optimization
        techniques, and much more at your fingertips. 

        L i s t s
        ~~~~~~~~~
        Lists of values may be used to create graphs or tables, and may also
        be used to represent rows or columns of matrices.  You can think of


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        lists as one-dimensional arrays.  TK finds a solution for the first
        elements in the lists, then the second elements, and so on.  F10,
        which is not functional in FREETK, is used to initiate a List Solve.

        F u n c t i o n s
        ~~~~~~~~~~~~~~~~~
        TK Solver Plus has three kinds of user-definable functions:  List
        Functions, Rule Functions and Procedure Functions.

        LIST FUNCTIONS are useful when the relationships between function
        values and arguments can be defined by two interrelated lists of
        values.  There are four types of mapping of function values and
        arguments available: table lookup, step mapping, linear interpolation
        and cubic interpolation.

        RULE FUNCTIONS are groups of rules which are called or referenced
        from the Rule Sheet and may, in turn, call or reference other Rule
        Functions and Procedure Functions.  Rule Functions simplify the Rule
        Sheet and enhance the clarity of long and complex models.

        PROCEDURE FUNCTIONS complement TK's approach to problem solving.  TK
        is a very high-level "declarative" language:  once the rules and
        constraints are declared, TK uses its powerful built-in algorithms to
        generate solutions for given problems.  The user-definable Procedure
        Functions come in handy when the built-in procedures cannot handle
        specific procedural tasks, such as finding the greatest common
        denominator of two whole numbers, numerical integration, or using an
        iteration technique different from the Newton-Raphson method.  TK
        Solver Plus comes with a library of Procedure Functions for numerical
        analysis, statistical computations, etc.

        Procedure Functions consist of a sequence of assignment and control
        statements which are executed unidirectionally -- essentially like
        programs written in conventional "procedural" languages such as
        FORTRAN, Pascal or BASIC.  Procedure functions may call or reference
        other Procedure Functions or Rule Functions.  Recursion is allowed,
        i.e., a Procedure Function can call or reference itself.

        G r a p h i c s
        ~~~~~~~~~~~~~~~
        Line Charts, Bar Charts and Pie Charts are available in CGA, EGA and
        Hercules graphics modes.  Pressing F7 (not functional in FREETK) is
        all that is required to display a plot.

        T a b l e s
        ~~~~~~~~~~~
        Values in lists may be displayed in tabular form simply by pressing
        F8 (not functional in FREETK).  Tables can also be used in
        interactive mode, meaning that changes in values of list elements may
        be made and a new solution found without leaving the tabular
        display.  Interactive tables effectively combine all the mathematical
        problem-solving power of TK Solver Plus with the convenience of a
        spreadsheet format.




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        Numeric Formatting
        ~~~~~~~~~~~~~~~~~~
        TK Solver Plus offers virtually complete control over the formatting
        of values on screen and paper.  More information about numeric
        formatting may be found in REFCARD.TXT in a section dealing with the
        Numeric Format Sheet and subsheets.

        Interface with other programs
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        TK Solver Plus will read and write files in WKS (Lotus 1-2-3), ASCII
        and DIF (Data Interchange Format) formats.



        How to get more information and more software
        ---------------------------------------------

        TK Solver is available from Universal Technical Systems, Inc. (UTS).
        Various versions run on the IBM PC/XT/AT and compatibles, Apple
        Macintosh, Apple IIe, DEC Rainbow, DEC PC350, Wang PC, and a variety
        of MS DOS machines (Texas Instruments Professional, Data General One,
        Canon, Toshiba, Zenith PC and others).

        For $25.00 we will send you a FREETK Follow-up Package including:
          -  "The TK!Solver Book" co-authored by the originator of the TK
             concept, Dr. Milos Konopasek,
          -  a diskette with 100 TK models for your FREETK, covering a wide
             variety of applications, and
          -  detailed information about TK Solver Plus.


                  Universal Technical Systems, Inc.
                  1220 Rock Street
                  Rockford, Illinois 61101

                  1-800-435-7887 (outside Illinois) 
                  1-815-963-2220 in Illinois and International
















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