# Category : Financial and Statistics

Archive : FREETK.ZIP

Filename : FTKINTRO.TXT

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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