PHY102 - Linux Help

The computers in room 346 Gilner are dual boot systems and can run either the NT operating system or the Linux operating system. Linux is a new form of the Unix operating system and it is becoming extremely popular, mostly because it works well and it is FREE. Unix is the most widely used operating system on workstations, whereas MS Windows is the the most widely used system on pc's. However Linux also runs on pcs and is eroding the monopoly of the windows system on that platform.

Your account

You have been assigned an account under the linux operating system of the computers in rm 346G. Your account name and initial password will be given to you by your TA. This week you need to:

Change your password

To start a ``terminal'' click the ``terminal'' (or it may be a small foot...not the one at bottom-left) on the control panel at the bottom of your screen (after logging in). At the prompt type:
yppasswd
Then answer the prompts.

Worksheets

Your worksheets are "postscript" files intended for viewing using "Ghostview" or for printing. First download the worksheet from the class web-page and save it locally. Ghostview can be started from the "foot" -> programs area or by typing "gv <filename>" at a command-line-prompt in a terminal window (click on the screen on the toolbar to get a terminal window). The worksheet can be printed out by selecting "print" under "file" in ghostview and hitting "print" (the default values should result in the file being printed on the 346 Giltner printer). It can also be printed directly from the command line in a terminal window by typing "lpr <filename>". Note, replace <filename> with the real filename!

Backing up: it is useful to make additional copies of your work in case it gets accidentally deleted or corrupted. I recommend creating a new directory call "backup" and periodically copying all your files to backup. This can be done using the "file manager" (click on "foot" to find this and start it) or using command line commands if you know what you are doing.

useful command-line commands:

"mkdir <directoryname>" creates a new sub-directory named <directoryname>
"cp <file1> <file2>" copies <file1> to <file2> where <file2> can be a new filename or a directoryname. e.g., "cp * backup" will copy everything in the current directory to the subdirectory named "backup", if backup has already been created as a subdirectory. Note: cp is a safe command in that it leaves copies of the files at the original location and doesn't delete them. However, it will overwrite files so if you copy a file to a new name and a file of that name already exists, it will be obliterated!
"cd <directoryname>" moves you to directory <directoryname>
"pwd" tells you what directory you are in
"ls" tells you what is in your directory
"rm <filename>" deletes <filename> BEWARE of rm, for example "rm * " deletes everything in your directory!
"man <utilityname>" gives (rather formal) help on utility <utilityname>. (e.g., try "man ls"). After accessing a "manual" page your terminal gets reformatted. To scroll through the pages hit "spacebar". To exit and get back the command line hit "q".

Run mathematica

Click on the "foot" on the toolbar at the bottom of the screen. Holding down the left mouse button, slide the mouse to highlight "programs" and let go of the mouse button. Then click on "applications"-> "wolfram mathematica". This will launch a Mathematica window.

Completing assignments

Complete assignments by typing information into your Mathematica notebook on the screen. Periodically save the notebook.
Click ``save'' which is under ``file'' in mathematica toolbar. It will save the file to the current directory under the linux operating system (give it a better name that ``untitled''!!). To ensure that you have succeeded, use the "file manager", or return to your ``terminal'' window and type ``ls'', to make sure that it is there. Saved notebooks can be reopened in Mathematica from the "file" menu. An assignment is completed when you have completed all the questions on the worksheet, correctly, in a Mathematica notebook and printed it out and handed the printed copy to an instructor or put it in Prof. Billinge's mailbox or under his office door.

Print your worksheet

To print your file, Click ``print'' under ``file'' in the mathematica toolbar. Then choose ``file''. This will save your file as a postscript file (again give it a better name that ``untitled''). Then return to the terminal window and type ``ls'' to check that it is there. Now type ``lpr filename.ps'' and your file will be printed on the printer in rm346G.

You can launch a window-based help system from the applications menu. If you plan to stay in a technical field such as physics or engineering you will benefit from learning more about the unix operating system and a nice unix manual is available online.

Time to go home, just for today...

To end your session and log out:
1) first save everything that you don't want to use
2) close all your applications. Strictly speaking you don't have to do this, but you will find things you forgot to save this way and won't lose them!
3) log out: "foot"-> "log out" then hit "Yes".