home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
The C Users' Group Library 1994 August
/
wc-cdrom-cusersgrouplibrary-1994-08.iso
/
vol_300
/
305_02
/
sample.doc
< prev
next >
Wrap
Text File
|
1990-02-14
|
10KB
|
262 lines
This document describes a sample session with Emandel and Emdisplay.
I ask that you read the full documentation MANDEL.DOC before
attempting to run Emandel. Then print out a copy of this file and
follow the step-by-step instructions for a complete "tour" of the
highways and byways of Emandel and Emdisplay. You should also print
out a copy of CMDS.TXT, which is a brief summary of the commands
available in Emandel.
Start Emandel by typing the following line at the DOS prompt:
EMANDEL -1.7186 0.0041 -0.0041 /S.2 /B3
Be sure you type the line exactly as above. When you see the word
"Working." appear on the bottom line, press ^S (control-S). This
will blank the screen. You can now wait for the computer to beep, to
tell you it has finished calculating. (This will take about 9 1/2
minutes on a 10 MHz AT clone with a math co-processor chip, but may
take an hour or more on a slow PC without a math chip.)
If you look very closely, you will see a tiny dot moving down the
screen. This shows you the progress of the calculation.
You may wish to check progress more closely from time to time before
calculation is done. Press ^S again to restore the screen. Actually,
in this particular picture there will be nothing to see until it is
about 2/3 done, at which time a small speck will appear, and then
nothing more until it is finished. This is because I have selected a
frame with mostly low-value pixels for a quick sample session.
You will know you have restored the screen, in the absence of an
image, because the prompt line will appear, unless you have erased
it. Now type ?t and then type ?% (letter commands may be upper case
or lower case.) The first will tell you the elapsed time and
(possibly) the estimated remaining time in brackets. The second will
tell you what percentage of the frame is finished. You may press ^S
to blank the screen again.
If you are out of earshot of the computer, and you want to know if
it has finished yet, un-blank the screen with ^S and look for the
words "Calculation completed." in the bottom line.
AFTER CALCULATION IS FINISHED THE FUN BEGINS:
Unblank the screen with ^S if you have not already done so.
Press ^T (control-T) to enter Threshview mode.
At the "Cluster?" prompt enter A <CR>
At the "Auto-draw. First cluster?" prompt press <CR>
At the "Last cluster?" prompt again just press <CR>
At the "Start value?" prompt enter 2 <CR>
At the "Size?" prompt press <CR>
At the "Gap?" prompt press <CR>
At the "Stop value?" prompt press <CR>
And before your eyes, a picture will appear. Next:
At the "Cluster?" prompt enter W <CR>
and the picture will be written to a file, and the prompt line will
tell you its file name and ask you to press any key. So press any
key and you will get the "Cluster?" prompt again. Now:
Enter A <CR>
At the "Auto-draw. First cluster?" prompt press <CR>
At the "Last cluster?" prompt again just press <CR>
At the "Start value?" prompt enter 2 <CR>
At the "Size?" prompt press <CR>
At the "Gap?" prompt enter 3 <CR>
At the "Stop value?" prompt press <CR>
A new picture will appear. Again:
At the "Cluster?" prompt enter W <CR>
And then press any key when you are asked to. Next:
At the "Cluster?" prompt enter 100 <CR>
The program will tell you that cluster 100 is clear and ask you for
a new bottom value. Enter 25 <CR>
The program will ask you for a new top value. Press the "less than"
sign (<), which is the same as the comma key, and then <CR>
And the picture will change again. At the "Cluster?" prompt enter W
<CR> again to write this third picture to a file.
Now press ESC to exit from Threshview mode.
Now press ^W (control-W) to write the data to a file, in case you
want to play with this file again before erasing it.
Now press ^C (control-C) to exit from Emandel.
NOW IT IS TIME TO USE EMDISPLAY
Start the program Emdisplay by typing at the DOS prompt:
EMDISPLAY
Or, if your printer is connected to LPT2 type instead:
EMDISPLAY /2
NOTE: There is no point in trying to print if your printer is not
Epson compatible, or if it is a daisy-wheel printer. But you can
still use Emdisplay to view pictures without printing.
Now the first of your pictures will show on the screen. Press the
space bar to see the next one. Or press B to see the previous one.
You can scroll around and around, forward or backward, as long as
you like.
If you wish to print one of the pictures, turn your printer on, put
a sheet of paper in it, align the top of the paper with the top of
the ribbon, and then press P. Because the pictures you just made are
small, there will be a lot of blank paper. The picture will be
printed in the middle of the paper with the title line at the
bottom. (As seen after it is done. While printing it is sideways.)
When you are finished, press X to exit from Emdisplay.
Now you have gone through your first session with Emandel and
Emdisplay, and you are ready to make the picture of the whole
Mandelbrot set. You will use this one later as a guide as you
explore its inner recesses.
-------------------------------------------
MAKING THE FILE "WHOLE.PIK"
This one will take longer. About 40 minutes on my 10 MHz AT clone
with a 10 MHz math co-processor chip. Perhaps all night on a slow XT
with no math chip. So you will want to run it when the computer has
nothing better to do.
So, when you are about to go to bed, or are not going to be using
the computer for a few hours, run the batch file WHOLE.BAT by typing
WHOLE
at the DOS prompt. When you see the "Working." prompt, press ^S to
blank the screen.
When you get up in the morning press ^S to un-blank the screen. If
"Calculation completed" appears on the bottom line you may proceed
as above to make pictures. (REMEMBER TO USE ^W TO SAVE THE DATA
FILE. You will use this one as a basis for future sessions. See the
instructions for Grid mode in MANDEL.DOC.) Otherwise:
Press ^Q to quit calculation. ("Calculation halted" will now appear
on the bottom line.)
Press ^W to write the data file. (The bottom line will say
"Saving..." while it writes to disk, and will say "Saved" when it is
done.) If the frame is well-along in its calculation, this file-
write will take some time. It is a BIG file. A full data file takes
15 seconds to write or read on a 28 ms. hard disk running in a fast
AT clone. If you are using a floppy disk (*** NOT RECOMMENDED! ***)
it may take 5 or 10 minutes.
Once the file is saved, press ^C to exit the program.
The data file is named WHOLE.PIK because that name was given on the
command line (in the batch file WHOLE.BAT).
When you are ready to resume work on the frame, run Emandel by
typing at the DOS prompt:
EMANDEL WHOLE
Do not run the batch file WHOLE.BAT again unless you have lost
WHOLE.PIK and want to produce it again from scratch.
You can halt the program, save the data file, and then re-start the
program as many times as you like, until it is finished. And after
it is finished, you can re-start it again using the completed data
file, in order to make more pictures with Threshview or to use Grid
to create new batch files.
-------------------------------------------
A SAMPLE SESSION WITH GRID MODE.
After WHOLE.PIK is finished, if you are not still in Emandel, run it
with the command line:
EMANDEL WHOLE
And when you see "Calculation completed" on the prompt line press ^T
to enter threshview mode.
At the "Cluster?" prompt enter A <CR>
At the "Auto-draw. First cluster?" prompt press <CR>
At the "Last cluster?" prompt again just press <CR>
At the "Start value?" prompt enter 7 <CR>
At the "Size?" prompt press <CR>
At the "Gap?" prompt press <CR>
At the "Stop value?" prompt press <CR>
The screen will re-draw. Wait for it to complete. You will now see
the narrow "halo" that surrounds the Mandelbrot set. It is this halo
around the set that contains all the interesting patterns you will
want to explore.
Now press ^G to enter Grid mode.
Press * (the asterisk) to increase hair-line speed.
Use the number pad keys to move the hairline to the region of the
halo. Remember that the 5 key stops movement if you are in glide
mode.
Press ^B to open a grid box.
Press <BS> to set motion speed to its minimum.
Use the number pad keys to position the grid box onto some part of
the halo.
Press # (the crosshatch) to tell Emandel to create a batch file.
At the "Enter PIK file name" prompt, enter a file name of your
choice (it must be a valid DOS file name of 8 letters or less, and
should not have a file type extension) or else just press <CR>
At the "Maxit?" prompt enter 255.
At the "Size" prompt enter 1 unless your computer's memory is
limited or you wish to save time by using a small frame size. If you
enter 0.25 the picture will be half the height and half the width of
the full screen.
Now the program will tell you the name of the batch file, such as
"EMAND0.BAT". Remember this name.
Now press ESC to exit from Grid mode and ESC again to exit from
Threshview mode.
IF YOU HAVE NOT ALREADY SAVED WHOLE.PIK PRESS ^W TO DO SO NOW. If
the file WHOLE.PIK was complete before you entered Emandel this
session, then you do not need to save it again.
Press ^C to exit from Emandel. If you have not saved WHOLE.PIK,
Emandel will tell you "file not saved. Exit?" Press Y if you already
have a completed copy of WHOLE.PIK on disk. If you have in fact
forgotten to save WHOLE.PIK press N. Then, when the prompt says
"Well okay then..." press ^W and when the save is completed press ^C
to exit from the program.
When you are ready to run Emandel again, type the batch file name at
the DOS prompt (without the "BAT" extension:)
EMAND0
This batch file (created in the above session) will run Emandel and
produce the frame you marked for enlargement. The batch file will
automatically delete itself if the program terminates without
errors.