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Physics & Astronomy
Unix Platforms

Logging On

You should have a password and a PIN for the door to TH 123, issued in the Physics and Astronomy Department office, TH 335; or you may have logged into th123-12 remotely with your P&A login account.

To log onto one of the Linux workstations, press the <enter> key, and the logon prompt should appear. Users should remember to leave the monitor powered on after logging out. (If someone left the computer logged on, log him/her out, below.)

Enter your user name. Then enter your password.
You can now execute system commands and run programs from the command line. Refer to the Unix Tutorial for some guidelines. However, most users will want to run jobs from the KDE desktop.

The P&A Unix/Linux systems use Kerberos for password management. Here's a pointer to MIT's documentation for the Kerberos authentication system.

Opening the KDE Desktop

This GUI provides a working environment similar to those of Windows or the Macintosh operating systems. To start the KDE desktop, enter the startx command from the keyboard:
	th123-33:bland% startx &
The desktop should load. On the taskbar at the bottom of the screen will be various icons. Click on the lower-left-hand button, then select an xwin terminal window. (There are various types of terminal windows; the instructions on this page have been tested mainly in xterm windows.) Experienced users usually keep several of these windows open at once. They can be used to edit files, read email, and start applications such as IDL, MatLab, Mathematica, and Unix utilities. Hint: you can change the font size by right-clicking the mouse with <ctrl> held down.


The recommended way to read your email is using pine. From a terminal window (or telnet or ssh), enter
	th123-33:bland% pine
The first time you run the program, it will ask to set up some files. Just say yes to everything.
This Unix program is not as glitzy as Eudora or MS Access. However, it has the advantage that your email remains on the Unix server, and you can always find it, from any workstation, from your computer at home, etc.
Notes on Email


The printers in TH123 are available to all P&A computer users. Both Unix/Linux machines and MS-Windows machines can spool print jobs to them. Refer to Printers for more details.


This feature lets you run MS-Windows 98 as an application running under the Linux operating system! (Yes, we DO still pay a license fee to Microsoft.) Most of the useful and endearing features of a PC running windows are reproduced here. (See WINDOWS SYSTEMS below.) In particular, the TH 123 printers are available, and Unix files can be mounted with Samba. The main desirable feature which is lacking is cut and paste between Linux and Windows. Such communication has to be carried out by saving files (text, jpegs, etc) on one system, then opening them on the other. It is also not possible to access the CD-ROM or floppy drive, or to install your own programs.

To access win4lin, connect to the server dunsel. (Contact the system administrator for a win4lin account on dunsel.)

	th123-32:bland% ssh dunsel
A window should open on your terminal looking just like the MS-Windows 98 screen. Log on, using your P&A Department logon and password. Now you should be able to use MS-Windows and MS-Windows-based software.


This famous do-your-thinking-for-you program is available to us in various ways, with the license conditions and availablility changing often.

Log onto one of the Linux stations in TH 123. Enter startx to run the KDE desktop.
Open a terminal window (icon on taskbar at bottom of screen), and run Mathematica:

	quark:bland% mathematica &
A Mathematica icon should appear at once in the lower left-hand corner of the desktop, and in a few seconds a Mathematica window will open. If you instead receive a message to the effect that the proper fonts are not installed, something is wrong. Try moving to another workstation. If this does not work, try this: when the message box comes up informing you that the proper fonts are not installed, try dismissing it by clicking on the square box in the upper right-hand corner of the dialogue box (rather than responding either "Continue" or "Exit"). This seems to work.

Here is a Mathematica command to enter, just to make sure that it is working:

	Plot[Sin[x], {x, 0, 4 Pi}]
After typing the rest, execute the instruction with <shift><enter>. (Just pressing the <enter> key moves to a new line, but does not execute the instruction.) A graph of two cycles of a sine wave should appear.
Mathematica Tutorial

Running IDL

This fortran-like programming package can be run directly on any of the Linux machines in TH 123, as well as on several other machines in the Department. Furthermore, any other computer on the internet can connect to one of the TH123 machines and run IDL.

IDL runs best from an xterm window. If you are not in a xterm window, open one as follows:

	th123-11:bland% xterm &
Now when you run IDL you will have the benefit of a buffer of previous instructions, accessible using the up-arrow key.

Here is a short IDL example. (The full path for IDL is /u5/idl/bin/idl .)

	th123-11:bland% idl
	IDL Version 5.5a (linux x86). (c) 2001, Research Systems, Inc.
	Installation number: 303259-1.
	Licensed for use by: California State University

	IDL> plot,indgen(100)
This should give a plot of a straight line. To save the plot as a jpeg graphics file:
	IDL> write_jpeg,´temp1.jpg´,tvrd()
This should leave a file named temp1.jpg on your working directory. It can be displayed on a web page or imported into a WORD document. To see what is on the file, you can print it out, and display it on the screen:
	th123-31:bland% ls *.jpg
	th123-31:bland% lpr temp1.jpg
	th123-31:bland% lpq -Php1 status
        th123-31:bland% xv temp1.jpg 
If you find another window blocking part of the graph, try turning the backingstore on, in the xwin32 configuration routine. For more about printing, see the link at the top of the page.

For a good pdf-based help facility, enter from any command line,

	th123-11:bland% idlman &
The Adobe Acrobat Reader should open with all IDL manuals available.
IDL Tutorial


MatLab is a programming and display package with very good graphics. To run it on any Linux machine,
	th123-21:bland% matlab&
Pretty soon a MatLab icon will appear, and later some windows will open. Figure out which one to type into (you may have to turn numlock off), and enter
This will make a nice plot, with interactive scaling, etc. You can export the figure as a jpeg file, then import it into Word, post it on a wep page, etc. MatLab should also print directly to the system printer, in TH 123.
MatLab Tutorial


In general (but for the first time you run StarOffice, see below) you can start the StarOffice program from a command line, by entering
	th123-33:bland% office &
(The ampersand detaches the task from the terminal window so you can use it later for something else before the office task terminates.) A sort of special desktop or window for the StarOffice suite opens, and you can launch the word processor, the spread-sheet program, etc. NOTE: The first time that you run StarOffice from your account, you have to do something special first. From a terminal window opened from the KDE desktop, enter the special command
	th123-33:bland% start-star-office
A setup program will run. Just fight your way through it via the path of least resistance. In the big Information box you should probably enter SFSU (for the institution), your name, and your email. Otherwise take the defaults. There will be a message about Java, asking if jdk1.3.1 or /usr/local/jdk1.3.1 is the correct location. It is. When the setup program exits, it will have created a directory named office52 on your main user directory, and will have created an alias for office which starts the StarOffice program. You can then use it as shown just above. The first time you run StarOffice itself, you will get a dialog box called Autopilot Internet Setup; just choose "Don't Use the Internet."
See Star Office Suite


  • IRAF tip:
    To print a graphics window (from inside imexam):
    when the cursor is a blinking circle inside an image window, type:
Further contributions will be appreciated...

Unix/Linux System Commands.

It is good to learn some of the basic commands used by the Unix/Linux operating systems, as directed from a command line (as opposed to a GUI interface). They are cryptically named and hard to learn about. Here are some of them. (The comment after the command is not part of the command and should not be typed at the keyboard.)
	th123-12:bland% ls	List the files and sub-directories of the current working directory.
	th123-12:bland% mkdir test1	make a subdirectory named test1
	th123-12:bland% cd test1     change to subdirectory test1
	th123-12:bland% pwd          print working directory
	th123-12:bland% who          List users on the computer
	th123-12:bland% man ls       man is the old-fangled help program.
	th123-12:bland% info ls      info is the new-fashioned help program.
	th123-12:bland% pico temp1.txt	Run the text editor pico

If you are unfamiliar with the Unix/Linux environment, refer to the Unix tutorial.

Logging Off the System

To close the desktop and log yourself out at the same time, first right-click with the mouse on the desktop background and select "logout"; confirm your intention in the dialogue box which pops up. NOTE: DO NOT select "lock screen". There is a bug in this feature which makes it impossible to unlock the screen afterwards.

After your graphics screen exits, you must also exit from your command-line login, by typing 'exit'.