file: mlabfiles.txt                      date: September 16, 2013

This is information for running MLAB under an MSWindows operating
system. You may want to print this text and keep it for reference.
Some details differ for Mac OSX and for Linux, but this information is
still valuable.

A Quick Example of using MLAB:
------------------------------

When you run MLAB, a "console" window is put on the screen, and a
smaller "start-up menu" window is displayed in which you must make a
selection. Actually, the first time you run MLAB, you will be asked
for a "user-name" that is kept just for display purposes before the
start-up menu is presented.  And later on, until you "register" MLAB,
you will be asked for an "authorization key-value" that you obtain
from Civilized Software.  When you obtain the authorization key-value
and enter it, you will never be asked for it again.  Until you obtain
your authorization key-value, you should enter "0". After responding,
the start-up menu window will be displayed.

One choice in the start-up menu window is to run various examples.
Another choice is to go to "top-level", which means that the menu
window is removed from the screen, and a "*" prompt symbol is
displayed in the console window; this prompt is waiting for you to
enter an MLAB command.

There are dozens of MLAB commands and hundreds of MLAB functions
waiting to be used. In essence, MLAB is an interpreter for a
high-level mathematical language and you use MLAB by specifying
purposeful sequences of MLAB commands to accomplish your end. (As a
practical matter, you will probably often enter these commands in a
text-file to construct a re-runnable 'script' called a do-file.)

You can define a function and graph it as follows.

 function f(x) = a*cos(b*x)*exp(-k*x)
 a = 1; b=4; k =.5
 v=1:10!100
 m= points(f,v)
 draw m
 view

Note 1:10!100 = 1:10:.0909090909, and 1:10:.0909090909 means the
column vector of values from 1 to 10 in steps of size .0909090909 (So
can you guess what 1:10!100 means?)

Also note points(f,v) = v&'(f on v), and v$'(f on v) means the
column-wise concatenation of v with the same-sized column vector
consisting of the values of f computed on the values in v.  (What do
you think the operator & does as opposed to &'?)

You can read-in 110 data values from a file into a 2-column matrix
as follows.  The result is a 55 row by 2 column matrix.

 d = read("filename",55,2)

Taking the rows of d as (x,y) data-points - with error in the y-values
- as data points "modeled" by the function f, defined above, you can
estimate the unknown parameters a,b,k as follows.

 fit(a,b,k), f to d

You can use estimated weights for the various data points in d based on
a moving variance estimation function ewt as follows.

 fit(a,b,k). f to d with wt ewt(d)

You can graph the data and the "fit" as follows.

 delete w  /* to discard any previous picture */
 draw d linetype none, pointtype circle
 draw points(f,d col 1) color green
 view

You can look at the derivative of f and graph it as follows.

 type f'x
 draw points(f'x. d col 1) color red
 view

Note MLAB uses symbolic-dervatives when derivative values are needed
during curve-fitting.

Also note you can fit (or just solve) differential-equation-defined
models in MLAB, so that chemical kinetics and physiological and
compartmental models can be handled.

Try this:  

 a=3.14159e200
 b= -(10e201)
 type a,b, a*b

Now try that with any other computational program you have access to.
(Can you see why this behavior is useful in curve-fitting?)

Note, you can probably see that you need to have the MLAB manuals
available because there is so much in MLAB that you will miss
otherwise. You can find a link at www.civilized.com that offers the
option to download the MLAB manuals in PDF format.

--------

The Executable Directory and the Working Directory:

There are two important directories (or "folders") that you must be
aware of when running MLAB.  The first is the "MLAB executable
directory", and the second is your "current working directory".

The "MLAB executable directory" is that directory where the MLAB
executable program file (and other MLAB system files) are stored.
This directory is established by the MLAB setup program which is run
when MLAB is installed.  Generally, this directory is C:\MLAB\ unless
some other directory was specified to the setup program.  In any
event, you MUST know the full path and the name of this directory.
You should write it on a piece of paper and tape it to your computer.
(MLAB prints-out this full directory name when it is run.)

Your "current working directory" is that directory where you want to
get your "input" and write your log-file and other output, at least
for "today".

When you run MLAB and ask it to execute a do-file, or read a
data-file, then, unless you specify a specific path as part of the
file-name (or set the FILEDIR variable,) the current working directory
will be the place that MLAB looks for such files. Thus the directory
where you keep do-files and data-files for some project is the
directory that you want to make your current working directory when
you want to deal with that project.

--------

In a Unix system, MLAB is run by starting a "terminal-emulator"
program (like xterm or Darwin) and then 'cd'-ing to the directory that
you want to be your working directory, and then running MLAB by typing
"MLAB" at the 'command-line'. ('cd' stands for 'change directory'.)

You can run MLAB the same way in a Windows system (almost). You start
a so-called DOS window (labeled a "command-prompt" window in XP,) and
'cd' to your desired working directory, and then run MLAB by typing
"MLAB" as the next command.  In this case, the working directory is
established as you want it.  Note, however, unlike in Unix, MLAB puts
its own "console" window on the screen wherein all MLAB commands are
entered and printed, and where text-output occurs.

Also, note that to run MLAB from the "command-line" in either Unix or
Windows, you must have the MLAB executable directory in your PATH
environment variable, or else you must specify the fully-qualified
name in order to run MLAB (e.g. C:\MLAB\MLAB).

Without any 'cd' command, when you run MLAB from within a DOS-window,
your current working directory will start-out being the directory
specifed as the "start-in" directory associated with the DOS or CMD
icon. By default, in XP, this "start-in" directory is
C:\windows\system32\.  [You may need to establish a "desktop shortcut
icon" for the cmd.exe program generally found in C:\windows\system32\]

There are two other ways to run MLAB in Windows.  One way is to run
the MS file-finder program (by clicking start -> find, or start ->
search) and "navigate" by clicking to the MLAB executable directory,
and then double-click on the MLAB executable file, mlab.exe, to run
it.  In this case, your initial working directory will be the same as
the MLAB executable directory.

The final way to run MLAB is to double-click on the MLAB "short-cut"
icon on the "desktop".  When you run MLAB in this manner, your initial
working directory will be whatever is set as the "start-in" directory
assocoated with the 'icon' (Clicking on the icon actually causes
windows to refer to a collection of files that tell it the full-name
of the associated executable file, and various other properties,
including the "start-in" directory.)

Generally the "start-in" directory associated with the MLAB short-cut
icon is the MLAB executable directory, but you can change this by
right-clicking on the MLAB short-cut icon, and clicking on the
"shortcut" tab in the window that pops up, and then changing the
"start-in" text-field to whatever you want it to be.  Thus, before you
run MLAB, you could do this to set the "start-in" directory, And you
would re-do this whenever your desired working directory is different
from whatever is set.

In all cases, MLAB will write a session log-file in the initial
working directory.  This log-file will be called "MLAB.LOG" (and the
earlier log-files found there will be renamed with the 'shifted' names
MLAB1.LOG, MLAB2.LOG, etc.) The session log-file is convenient. You
can print it to obtain a record of what you did.  You can extract
text from it to construct a do-file.  And you can review error messages
to "debug" an MLAB do-file.

Even if you start MLAB with the MLAB executable directory as the
initial working directory, you can, in effect, change directories at
will as you use MLAB.  There is a control variable in MLAB called
FILEDIR.  This variable is a string of text that is prepended to every
file-name you refer to in your MLAB session!  [Your session log-file,
MLAB.LOG, will, however, by created in the initial working directory
that is set or that MLAB is given by Windows.  Setting FILEDIR has no
effect on where the log-file is.]

The FILEDIR variable starts-out as the empty-string.  Thus, assuming
FILEDIR is empty, if you type 'DO afile' in MLAB, you are referring to
the file afile.DO in your current working directory.  If, however, you
set FILEDIR - for example: FILEDIR = "C:\project1" (or FILEDIR =
"C:project1\") and then type 'DO afile', you will be asking MLAB to
execute the do-file 'C:\project1\afile.DO'.

The same prepending of FILEDIR occurs for all files you refer to in
MLAB.  Thus, for example if you read a data-file into a matrix with
the command 'm = read(dfile,120,2)', you are actually asking MLAB to
read the first 240 numbers found in the file dfile.dat within the
directory specified by FILEDIR into the 120-row, 2-column matrix m.

There is an exception to the FILEDIR prepending rule in MLAB for
do-files.  If the MLAB control variable DOFILEDIR is set to a
non-empty string, then this string, rather than FILEDIR is prepended
to any do-file name that is specified to MLAB.  (This lets you access
do-files in a particular directory (specified by DOFILEDIR), while
accessing other files in some other directory (specified by FILEDIR.)

Thus, if you have your "project" data-files and do-files stored in
some specially-named directory (and it is generally a good idea to
work in this way,) then the first command you should execute in MLAB
is: "FILEDIR = "xxx", where xxx is the fully-qualified path to the
desired working directory.  (Remember, you can change your working
directory at any time in an MLAB session by resetting the FILEDIR
string control variable appropriately.)

When you run MLAB, a "console" window is put on the screen, and a
smaller "menu" window is displayed in which you must make a
selection.  One choice is to run various examples.  Another choice is
to go to "top-level", which means that the menu window is removed from
the screen, and a "*" prompt symbol is displayed in the console
window; this prompt is waiting for you to enter an MLAB command.

Once you are at "top-level" and able to enter MLAB commands, you can use
the up-arrow and down-arrow keys to "scroll" back through the previous
MLAB commands and responses. Hitting the Enter key will take you back
to the 'current' prompt line. (You will note there are no scroll bars
on the MLAB console window; the arrow keys are the way you "scroll"
in the MLAB console window.) 

In addition to looking at the previous lines in the console window,
you can "select" a line by hitting the Insert key. This will cause the
selected line to appear at the 'end' of the console window as the
subject of a simple single-line editor facility.  You can then modify
the selected line, and hit the Enter key to execute it.  (When you
enter an MLAB statement which is malformed in some way, you will
receive an error message and the malformed line will be re-displayed
in the single-line editor facility where you can (attempt to) repair
the error and re-execute the line.)

=================================================

MLAB reads, writes or otherwise uses the following files or types of
files.

--------

1 - gxfonts.0: a binary file containing the 34 MLAB stroke font
definitions.  gxfonts.0 is a read-only file and found in the
directory where the MLAB program file is located.  The file is
accessed whenever a title string or axis label is to be drawn in
the MLAB graphics window.

--------

2 - mlab.hlp and mlabref.hlp: files containing text used by the MLAB
HELP systems.  These read-only files are found in the directory where
the MLAB program file is located.  mlab.hlp is read when either the
commands "HELP" or "HELP topic" are given by the user.  

The file mlabref.hlp is read when the user strikes the F1-key to
access the special Windows help presentation system.  (This text is
not very useful.)

Also the content of the MLAB help-file, mlab.hlp, that is accessed via
the "HELP" command, although useful, is incomplete, and sometimes
wrong, so be sure to depend on the MLAB reference manual as the final
authority.

--------

3 - mlab.log, mlab0.log, mlab1.log, and mlab2.log: These are ASCII
text files containing the dialog of the current MLAB session (in
mlab.log) and the previous three MLAB sessions (in the files
mlab0.log, mlab1.log, and mlab2.log).  These files are created by MLAB
in the user's working directory and are useful for seeing a record of
MLAB results.  They are also useful for constructing .do-files, since
you can copy the text in an mlab log-file and edit it to construct a
do-file. It is also useful to look at an mlab log-file to aid in
debugging an mlab do-file.  (Note: see the definition of the system
variable ECHODO, below.)

--------

4 - .do-files: An mlab do-file is an ASCII text file containing
comments and MLAB commands, i.e. a 'script' in the mlab language. Such
a 'script' can be repeatedly re-run, and also easily changed as
desired.  Constructing and running a do-file is the preferred way of
using mlab whenever you have a relatively substantial computation to
do.  An example of a .do-file is the file DIMER.DO in the directory
containing the MLAB program file. Also there are example .do-files in
the MLAB\EXAMPLES\ directory.

A do-file can be generated with any ASCII text editor, such as
the MSWindows Notepad Accessory program.

The MLAB command: [EDIT FILE filename.do] will run the Notepad
program for editing the specified new or existing .do-file
from within an mlab session..

When running the Notepad editor via the EDIT FILE command within mlab,
the named .do-file is searched-for or created in the directory
specified by the path in the DOFILEDIR control string. If DOFILEDIR is
null, then the directory specified by the path in the FILEDIR control
string is used. If FILEDIR is null, then the initial "start-in"
working directory is used..

MLAB .do-files contain MLAB commands and comments.  Comments begin
with the 2-character sequence: /* and are terminated with the
2-character sequence: */.  Comments may span multiple lines. Note,
comments may NOT be embedded within enclosing comments.

If more than one MLAB command appears on a line of a .do-file,
they must be separated by semicolons (;). (There are other
situations where terminating semicolons must be used as well.)

An MLAB .do-file is executed by the command: [DO filename.do];
that's why it is called a do-file.

The three scalar control variables DOSTEP, ECHODO, and CASESW
control aspects of general mlab execution and .do-file execution.  

If DOSTEP = k (a positive integer), then MLAB will
pause--waiting for a key to be struck by the user--after every
k lines in the .do-file have been executed.  Thus, DOSTEP=1
will allow you to "single-step" through the do-file, perhaps,
looking for a line that cause an error messsage.  If DOSTEP =
0, which is the default case, then a DO-command will run the
specified do-file without interruption to completion, unless
MLAB commands requiring keyboard input are encountered, or
there is an error detected.

The control scalar ECHODO controls the "echoing" of do-file commands
to the screen and the log-file, mlab.log.  If ECHODO = 0, then
the .do-file is executed silently--no commands are echoed to
the screen or the log-file; if ECHODO = 1, then the lines of
the .do-file are echoed to the screen but not the log-file;
if ECHODO = 2, then the .do-file is echoed to the log-file
but not the screen; and if ECHODO = 3, the do-file is echoed
to both the screen and the log-file.

The control scalar CASESW controls the case-sensitivity of
MLAB names.  If CASESW = 0, then upper-case characters are not
distinguished from lower-case characters; all input is
converted to upper-case, except within quoted-strings.  If
CASESW = 1, no such conversion is done, except for control
variable names, mlab function names, and mlab reserved syntax
words, like "TYPE" or "DO".

The implication of using CASESW =1 is sometimes subtle, especially
with identifiers used as filenames, and we reccomend you keep CASESW
set to 0. (MLAB generaly tries both upper-case and lower-case versions
of filenames in an attempt to not disappoint the user.)  .

--------

[How to Use MLAB]

The most convenient way to run MLAB when you have a repetitive or a
complex computation to do, is to setup a do-file to do it.
(Remeber you can do this by typing EDIT FILE xdofile.do to create
the do-file xdofile.do in your working directory.)

You should be sure to put comments in your do-file to define all the
variables and functions, etc. and don't forget to include comments
specifying the units for all data where this is important.

Note, it is convenient to give the commands "reset; echodo=3" as the
first commands in your do-file. Also, remember the READ, READON,
KREAD, and SREAD MLAB functions.  Another tip is that you can
construct strings by concatenation and you can execute such a string
containing a sequence of MLAB commands as a do-file!  For example, try
z=99; S="type "+"value of z:"+z; do S; and you can construct more
elaborate and useful examples.  [You should look at the file
startup.do and the do-files provided in the examples sub-directory.]

After your do-file is written and saved on disk, you should print it
(You can use the MLAB command "PRINT FILE xdofile.do" to get this
listing.)  Then you should read your do-file, add more comments, and
verify that it does what you want to the best of your ability.
(Remember to keep the MLAB manuals close at hand.)  After you have
iterated this step as much as you feel is helpful, you should then run
MLAB and use the command "DO xdofile" to run your do-file.  (Remember
you will need to have set-up any data-files or other do-files that
your do-file reads.

It is quite likely that there will be errors in your do-file.  If you
can see what the problem is, you can just tyoe "EDIT FILE xdofile.do"
and fix your do-file and resave it on disk.  [You should leave the
NotePad editor window 'open', so you can use it again in a few
moments.]  Then you can just type "DO xdofile" again, and see what
happens.  You can "flip" back and forth between NotePad and MLAB,
until your do-file is "debugged".

Sometimes it will be helpful to put TYPE statements in your do-file so
it will tell you the progress of execution.  This is just one of the
standard debugging devices that can sometimes be helpful.

When your do-file is debugged, it can be run whenever you wish
by running MLAB and typing "DO xdofile".

Of course, for all your work with MLAB, you must be aware of your
current working directory and have FILEDIR set appropriately.

All the examples that are available to you from the start-up menu are
just .do-files that that are stored in the sub-directory 'EXAMPLES' in
the MLAB executable directory (generally C:\MLAB\).  You should go
look at those .do-files (using Notepad, or using the 'type' command or
'edit' command in a DOS-window.)

One of the interesting things you will see in some of the example
.do-files is how to use the 'MENUCHOICE' and 'GETSTRINGS' MLAB
functions that allow you to make your own menus and to obtain text
input. (See in particular the Hogkin-Huxley Nerve Axon Model example.)
There are many other interesting "lessons" to be found in the
example .do-files as well.

--------

5 - .dat-files: .dat files are plain ASCII files containing numbers to
be read-in as data; the READ command is used to do this.  Examples of
.dat-files appear in the MLAB\EXAMPLES\ directory. (The READ command
scans the specified file for numbers given by ASCII characters in any
"standard" form, such as 123 or 12.34 or -3.1e12, etc.  All other
bytes are ignored; thus the mlab READ command can read appropriate
non-ASCII files too.)

As with .do-files, .dat-files can be created or modified with
any ASCII text editor, such as the MSWindows Notepad Accessory
program.  And, as with do-files, The MLAB command: EDIT FILE
<filename.dat> can be used to construct or change a dat-file.

Note, the MLAB string variable DOFILEDIR only affects the path
for .do-files, and does not affect the location of .dat-files
so that .do-files and .dat-files can be read from different
directories.

A .dat-file can also be created using Notepad, or any other program as
long as it contains the numbers you want (and only those numbers) in
ASCII (i.e. .txt format.)  DO NOT TRY TO READ MS-WORD or EXCEL FILES
IN MLAB UNLESS YOU KNOW THEY ARE TEXT FILES.  Files created by MS-WORD
and by EXCEL are generally not text files unless you know how to save
them, they are usually binary files. (and remember "rich text" is NOT
text!)- use Notepad or some other editor that can save plain ASCII
.txt files easily.)

The numbers in a .dat-file are read and stored as the elements
of a matrix M by using the READ command:

M = READ("filename.dat",nr)

This READ-command will read nr or fewer values from the file
filename.dat in the implicit directory (either specified by FILEDIR or
established at initial start-up.) The i-th successively-read value is
assigned to M[i] (so M will be a one-column matrix.).

The input file will be scanned for numbers embedded in ANY non-digit
text.  However, you can prevent any text you want from being scanned
by enclosing it in "'s or by the C-comment brackets /*, */.

When FILEDIR is null, the read command [M = READ("C:\DX\DY\S.DAT",
rr)] reads rr numbers from the file C:\DX\DY\S.DAT into M as a single
column of rr values. (If the file does not contain rr numbers, then
all the numbers present will be read.)

Data matrices with nr rows and nc cols can be
constructed with the following command:

M = READ("filename.dat",nr,nc)

If a .dat-file contains values for more than one matrix, a
special version of the READ command can be used. the
READON command can be used sequentially, as:

M1 = READON("filename.dat",nr1,nc1)
M2 = READON("filename.dat",nr2,nc2)
.
.
.
MN = READON("filename.dat",nrn,ncn)

Each READON command continues reading in the input file where the
previous READON command left-off.

There are other MLAB data-input commands you should learn about -
notably the KREAD and KSREAD functions.

--------

6 - .ps or .lj-files: A .ps file is an ASCII file in the Adobe
PostScript graphics language.  A .lj file is a binary file
containing or Hewlett- Packard PCL language. Both forms of
output files are called "plot-files".  They contain the
printer commands for an MLAB graphics picture.

After creating an MLAB 'picture' (consisting of one or more
MLAB "windows" all within the main mlab graphics window, using
the DRAW command, etc.), the MLAB-command [PLOT] will generate
a plot-file in the current working directory. This plot-file
is either a file named MLABP#.PS containing commands suitable
for printing on either a PostScript-capable printer or
a printer on a computer with appropriate conversion software
like Ghostscript, or it is a file named MLABP#.LJ containing
HP PCL-GL/2 commands suitable for printing on a GL/2-compatible
printer.  the symbol # denotes the next succesive integer in
the sequence 0,1,2,... (e.g. the first PLOT command writes-out
MLAB0.PS, the next PLOT command writes-out MLAB1.PS, etc.)

If the MLAB control variable PLOTDEV is set to PSL (or "PSL" -
try typing PSL) then a .PS plot-file is created containing a
black and white, Landscape orientation Postscript picture.)

If the MLAB control variable PLOTDEV is set to PSCL (or "PSCL"????)
then a .PS plot-file is created containing a
color, Landscape orientation Postscript picture.)

If the MLAB control variable PLOTDEV is set to HPLJ (or
"HPLJ") then a .PS plot-file is created containing a black and
white, Landscape orientation PCL-GL/2 language picture.)

An MLAB .PS plot-file can be converted to a so-called
'Encapsulated Postscript' file suitable for embedding in a
"document" file such as an MSWord file, or a .tex file by
editing the file to change the Landscape orientation of the
MLAB graph to a Portrait orientation and to respecify the size
of the picture.  This is done by editing the MLAB graphics
file as follows:

1- "open" the plot-file (MLABP0.PS say) with an ASCII text
editor (or with the MLAB command: EDIT FILE MLABP0.PS),

2- goto to the fifth line in the file, that contains the
text defining the bounding box given in 'point'-units
(1 inch = 72 points) that encloses the graphical image:

%%BoundingBox: 19 19 593 773

3- exchange the order of the last two numbers corresponding
to the width and height in point-units, so that the line
reads:

%%BoundingBox: 19 19 773 593

(This changes the picture to have the size appropriate
for "portrait orientation".)

4- goto the 32nd and 33rd lines of the file, that read:

612 0 translate
90 rotate

and insert a %-character at the beginning of these two lines,
leaving:

%612 0 translate
%90 rotate

(Lines in PostScript files beginning with a SINGLE percent (%)
character are treated as comments and ignored. This drops the rotation
of the picture that MLAB inserted to leave it in "portrait
orientation".)

5- save the file to disk with the name MLABP#.EPS (not .PS).

The 'encapsulated PostScript' file, thus created should be saved with
the filename extesion .EPS. It can be "imported" to MicroSoft Office
(Word, PowerPoint, Excel) or TeX 'documents' (i.e. files).

For example, to add the MLAB graph in the file MLABP0.EPS to an MSWord
document, position the text cursor in the MS Word document where the
graph is desired, goto the "Insert" menu, select "Picture" from the
drop-down menu, select the "FromFile" option, select the MLABP0.EPS in
the resulting FileSelect dialogue box, and then select "Convert File
From Encapsulated PostScript".

--------

7 - .lst files: ASCII files containing MLAB data names and data.

The MLAB PRINT command:

PRINT [name1,name2,....] in <filename.lst>

generates an ASCII text file named 'filename.lst' in the current
working directory containing the MLAB data names name1, name2,
etc. and their corresponding values.

If the mlab control variable NAMESW = 0, then the MLAB data names are
suppressed in the output file.  This provides a convenient way, for
example, to "export" an MLAB matrix to another computer program that
accepts ASCII data files.

Note, the MLAB command:

PRINT FILE <filename>

sends a command to the local printer, to print the named file in the
current working directory.

--------

8 - .sav files: A .sav file is a binary file containing "saved"
MLAB data names and values.

The entire current state of MLAB, including all control variables and
user-created curves, windows, functions, matrices, scalars, etc., can
be saved in a .sav file in the current working directory by the
command:

SAVE IN <filename.sav>

The saved state of MLAB can then be restored at any other time and in
any other MLAB session by typing the command:

USE <filename.sav>

The SAVE command can also be used to save specific MLAB data
structures, such as an MLAB graphic window named Q and a scalar vaule
named B by listing the specific data items to be stored; for example:

SAVE Q,B IN <filename.sav>

The window can be restored in a later MLAB session by typing the
command:

USE <filename.sav>

.SAV files are binary files; they can not be edited directly with
ASCII editors and are not exchangeable across different types of
computers; i.e. a .SAV file from Windows MLAB can not be easily
transferred to a non-Intel Macintosh version of MLAB due to the
"endian" conflict.

The pre-defined .sav-file DW.SAV defines the elements of the default
MLAB graphics window, W, and provides an example of a .sav file.
DW.SAV is generated by giving the MLAB commands (we do this via a
do-file):

WINDOW 0 TO 10, 0 TO 10 ADJUST WNICE IN W;
XAXIS 0:10!6&'0 LABEL 0:10!6 LABELSIZE .015 FFRACT OFFSET (-.01,-.025) \
FFRACT FORMAT (-3,5,0,0,2,0) PT UTICK IN W;
YAXIS 0&'0:10!6 LABEL 0:10!6 LABELSIZE .015 FFRACT OFFSET (-.09,-.01) \
FFRACT FORMAT (-3,5,0,0,2,0) PT RTICK IN W;
FRAME COLOR VIOLET IN W;
IMAGE COLOR BLUE IN W;
SAVE W IN DW

When drawing in MLAB without specifying the target MLAB "window", the
default MLAB-"window", W, will be used. MLAB obtains W by USE-ing it
from DW.SAV.

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9. - Printing Files on a Windows system.

The MLAB command:

PRINT FILE <filename>

sends a command to the local printer, to print the named file in the
current working directory.

The PRINT FILE works for ASCII files, such as .dat or .lst files, and
it also works for .lj files if you have a directly-attached HP
PCL-language printer (most printers understand the PCL language.)

This also works for .ps files if you have a directly-attached
Postscript-language printer.  (If not, you may need to use a
web-browser to view .ps files generated by MLAB.  You may be able to
print them via the web-browser program.  Also, if MSWord is properly
programmed with the analog of the Ghostscript Postscript to PCL
converter, you may be able to view a .ps file via MSWord.)

Also, you can send a file to your printer to be printed with the
command "COPY <file> LPT1:" given in a DOS command window.  The file
must be an ASCII text file, or in a native language of the printer.

========================

Some More Information about Using MLAB


1. How to draw and plot a 3-D surface picture.

The easiest way to see a 3D surface, when that surface is the surface
of a proper function, is to look at a corresponding contour map. See
the contour-map example found in the MLAB examples reached from the
MLAB start-up menu.

The "fancier" way to do this is as follows.

...

If you are "plotting" an MLAB hidden-surface picture, you should use
PLOTDEV = PSCL.  This will render correctly on both a color Postrceipt
printer, and on a black and white Postscript printe (via grey-scale
dithering matching the specified colors.)  A PCL-language printer
cannot (currently) be used to render an MLAB hidden-surface picture.


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