World of Education/World of Education.iso/world_f/feedback.zip/GENERAL.DOC

Text File | 1991-03-25 | 10KB | 210 lines

PEANUT software should run on all IBM compatibles.  It
is only necessary that the appropriate graphics
interface file be present.  If these programs are
copied, it is therefore important that the appropriate
file *.BGI be copied, too.  The programs automatically
try to select the finest graphics mode; to override the
default selection, press Ctrl-G (this will be necessary
with the ATT 6300, for example).  The programs are
compiled with Borland's Turbo Pascal, version 5.5.  If
the host computer has a numeric coprocessor (in other
words, an 8087 chip), these programs will try to take
advantage of it.  Most of the programs have associated
documentation files *.DOC; you are reading one now!

Interaction with the computer takes two forms:   Either
the user is making menu selections or else the user is
providing buffered input (that is, numbers or names).
In the former case, no ENTER is required - touching a
single key (perhaps in combination with the Ctrl key)
does the job.  In the latter case, however, the computer
has to be told when the input is complete, and this
requires ENTER as a signal.  When the computer is
waiting for this type of input, a box will open up on
the screen, into which the necessary information is to
be typed.  One may edit the data in the box, using the
left and right arrow keys to move the cursor.  If the
first keypress of an editing session is not an editing
keypress (an arrow, say), the input box is emptied.

There are a few standard control-key codes.  For
example, Ctrl-C clears the graphics window, Ctrl-P is
for printing, Ctrl-W gets the window reset menu, Ctrl-F
gets function library menus, and Ctrl-END ends programs.
If one tires of the random message melodies (there are
361293 of them), Ctrl-O switches the sound off (or on).
Other Ctrl-keys are described below.  Alt-C allows the
user to assign new values to the twenty-six variables
A..Z.  Pressing the desired letter displays the current
value of that letter, and pressing = activates the input
process.  In each program, Ctrl-K calls up a menu of all
the available special keys.  These keys are usually not
mentioned elsewhere in the menus.

Whenever the program is in a scrolling mode (the arrow
keypad used to examine a text or a table), one can
request a search by pressing ENTER.  The program finds
the first instance of the string you enter, and places
it in the window, usually on the top display line.  The
search is not case-sensitive.  For example, to scroll
through THIS file, together with a program-specific help
file, just press ?.  The necessary *.DOC files must be
found in the current directory.

The function interpreter built into the programs has
been taught to understand most elementary function names
(sin, cos, tan, csc, sec, cot, ln, log, exp, sinh, cosh,
tanh, arcsin, arccos, arctan, int, sqr = square root,
abs, and !) as well as some unconventional ones:
root(n,x) = nth root of x; pow(n,x) = nth power of x;
iter(n,f(x)) = n-fold iteration of f(x); max(a,b,..);
min(a,b,..); sgn(x) = x/abs(x); frac(x) = x-int(x);
binom(n,r) = n!/r!/(n-r)!; join(f|c,g|d,...,h) =
function defined by y=f(x) for x<=c, y=g(x) for c<x<=d,
..., and y=h(x) for remaining x-values; sum(b,f(n,x)) =
sum of f(n,x) for n=0 to n=b; prod(b,f(n,x)) = product
of f(n,x) for n=0 to n=b.  In the latter two cases, the
indexing variable defaults to n and the starting value
defaults to 0, but both can be adjusted by means of the
Ctrl-Function library menu.

If the host computer is new enough, the user will be
able to choose between pi and Ctrl-P, sqr and Ctrl-S,
and sq (or ^2) and Ctrl-E; these Ctrl-key presses insert
the correct graphics characters into the text.

It is required that parentheses be used in function
calls.  The user is permitted to add to the library of
function names, by calling up the New Names submenu of
the Function library menu.  Each new function name is
limited to six alphabetic characters (no numerals).  The
variables used to define the new functions are of no
significance; OSC(T)=SIN(1/T) produces the same result
as OSC(X)=SIN(1/X), that is.

The usual signs of algebra are used.  Exponentiation may
be denoted ^.  The multiplicative * can usually be left
out.  For example, 2x is interpreted to mean 2*x.
However, pix is not read pi*x.   Any letter can be used
as a numerical variable, and assigned a specific value
at any time, via the Alt-C option (see above).  For
example, axx + bx + c stands for a general quadratic
function, whose coefficients may be adjusted at will,
without the necessity of retyping the formula every
time.  Any string of letters and numbers will be treated
as a product of constants and variables, if it is not
found in the library of function names.  In particular,
note that xpi is read as x*pi, whereas pix is read as
p*i*x.  The process of translation starts at the left
end of every string.  Upper and lower cases are not
distinguished.  Brackets, braces, and parentheses may
all be used as grouping symbols.

It is occasionally convenient to be able to enter
numerical input in non-decimal form;  sqr(3) instead of
1.732, 2pi instead of 6.28, etc.  This is usually
allowable.

In many of the graphics programs, it is desirable or
necessary to move the viewing window around or to change
its size.  This is done by adjusting either the Width of
the frame or the coordinates (Horiz and Vert) of the
Center.  For blowups, there is a rigid tenfold Zoom
window.  When coordinate axes are showing, it is
occasionally necessary to regulate the scale markings on
the axes, by means of the Units/tick settings.  For
example, setting Horiz = pi/2 might be desirable when
graphing trigonometric functions.  For another, if the
viewing window showed x-values from -60 to 120, it would
be of no use to have 180 divisions marked on the x-axis.
In this case, one could simply direct the computer to
mark every tenth one (Horiz = 10), which produces a less
confusing image.  In fact, if a window request causes
the program to mark more than about fifty tick marks on
an axis, it will automatically adjust the setting for
that axis.  One may compress or expand the vertical
Scale, relative to the scale on the horizontal axis.
One may also blow up a (small) portion of the window
with a Flexible window, defined by Marking one corner
and then moving to the opposite corner and pressing
ENTER.  Because the shape of the resulting box is
variable, this procedure will necessarily distort the
vertical scale.  When you are done with the tiny window,
the screen can be restored to its nominal appearance, by
pressing Default in the main Window menu.  It is also
possible to define a window by specifying the four
Extreme values of the variables.  This will probably
also distort the vertical scale.

Sending images to your printer is fairly easy, unless
you wish to avoid the built-in distortion that computing
machinery produces.  In other words, your circles may
not look like circles, and perpendicular lines may
appear to be non-perpendicular.  It is possible to
compensate for this effect by adjusting the Vertical
scale in the Window Change menu, but only before the
drawing is done.  You will have to experiment a bit.
The unfortunate rule is that drawings can appear correct
either on the screen or on the printer, but seldom on
both.  Overhead projection devices complicate matters
even more.

Most procedures are interruptible.  If you do not want
to finish a drawing (or a game) in progress (whether on
the screen or on your printer), just press Esc.

In the event that a program creates files, the program
will prompt the user for filenames, and it will
understand if files on other drives are specified.  For
example, an elaborate geometric construction could be
stored as B:GOLDEN, which tells the computer not only
what the file is to be named (GOLDEN), but also where
the file is to be placed (on drive B).  This also
applies to file retrieval, of course.  Do not include
extensions in your filenames -  they will be ignored.
(Each program assigns special extensions.)

Some of the plotting programs are equipped with a menu
that allows one to add text to diagrams.  This feature
is activated with the Ctrl-Add/Del Text key.  The
displayed text string can be placed anywhere in the
figure.  When you request Write, the text is centered at
the cursor position, and stored as part of the figure;
when you request Erase, it is removed from the record.

Many of these programs are equipped with small pop-up
windows, activated with the function keys F1 .. F4, and
deactivated with Ctrl-F1 .. Ctrl-F4.  Side-by-side
comparisons of related graphs are thus made possible.
Windowing commands (issued through Ctrl-C or Ctrl-W) are
always applied to whichever of the five windows is
currently active.

If your graphics card allows, the programs will run in
color.  The Ctrl-H key calls up a color menu.  Tapping
the spacebar cycles through other color combinations for
the frame, text, and message colors, randomly assigned
when the program starts.

Printer support is provided for the standard dot-matrix
printer, as well as the Hewlett-Packard LaserJet and
PaintJet printers. To get the printing menu, use Ctrl-P.
The Device switch steps through the available printers.
The Region switch selects how much of the screen is to
be copied: everything, or else just the graphing window.
One may also associate specific screen colors with
printed colors (black, white, and shades of gray for
printers that can not produce color).  For simple black-
and-white images, there should be no need to change the
default settings; just press P for action.  If the
program does not detect a printer online, it will tell
you so.

This program is in a state of perpetual revision.  You
may obtain an up-to-date copy at any time by sending a
formatted diskette (360K, 720K, or 1.2M) and a prepared
mailer to
      Richard Parris
      Phillips Exeter Academy
      Exeter NH         03833
Comments and suggestions welcome.  Tel: [phone]