HMC Mathematics Computing Weblog

The time has come to switch off non-SSL mail service, and I will do so on July 31, 2010. Using SSL protects your password (and the security of our systems) as well as your mail. We currently allow non-SSL IMAP and POP connections, but there are only a couple of people using non-SSL IMAP and all the non-SSL POP connections appear to come from Google's GMail, which supports SSL.

If you're not sure whether you're using SSL or not, check your e-mail account settings. If you have a "use SSL" checkbox and it's checked, you're good. You can also check to be sure that you're using port 465 for SMTP (outgoing mail); port 993 for IMAP; or port 995 for POP.

While you're at it, if you're using POP, which pulls the messages off the server and maintains them on the machine you pull to, you might consider using IMAP, which leaves your mail on our server instead. IMAP is especially useful if you access your mail from several locations (e.g., a desktop machine, a laptop, a phone). POP is good if you just want to pull your mail off our server into another mail client (and is the only option that GMail supports for retrieving messages from other systems).

More details about configuring your mail clients to work with your HMC Mathematics Department accounts is available from http://www.math.hmc.edu/computing/support/email/.

You may need to install our self-signed root certificate to allow you to use SSL. Details are available from http://www.math.hmc.edu/computing/security/certificates/.

I have upgraded ponder to CentOS 5, bringing it into line with the other Linux workstations the department maintains. There shouldn't be any dramatic changes between CentOS 3 and CentOS 5, except that the current versions of various commercial software (notably MATLAB) will now run on ponder.

There are almost certainly some differences between the packages loaded on the current system and those on the old system; should you encounter a missing package that you need, let me know and I'll try to get it installed.

I've made various changes to the TeX set up over the last couple of weeks.

TeX Live 2009 and the Shared TEXMF Tree

The big change is that I've pushed TeX Live 2009 out as the current TeX system on the Linux and Mac OS X systems. We had been running TeX Live 2008 until the end of the semester.

I have also changed the shared TEXMF tree to use /shared/local/texlive/texmf-local rather than the old location (/shared/local/share/texmf), which is no longer accessible. The latest version of local packages and classes will now be available from /shared/local/texlive/texmf-local.

TeX Live 2010 Pretest

I am also maintaining an install of the TeX Live 2010 pretest distribution (Release Notes). TL 2010 is under active development, so at any given time it might have problems that you won't see in TL 2009. The developers welcome bug reports, but if you find a problem, please let me know before you file a report. I will update the distribution to make sure we have the latest version and let you know; you can then try your document again to see if the problem still exists.

TL 2010 is aiming for a code freeze in July. I'm not yet sure whether it will be ready for us to use in the fall semester, but I have my fingers crossed. If it is ready, I will make it the default on the Linux systems and also update the local installs on our Macs.

If you want to try TeX Live 2010 (on Linux or Mac systems), you can add the path to the binaries to the head of your PATH. I recommend that you do not add the path in your startup files so that you will get a known working version of TeX by default and get back to it by logging out and back in (or by closing the terminal window where you set the PATH).

You'll need to set the right architecture to make things work; I recommend you run one of the following commands to set the PATH correctly:

For the tcsh or csh:

setenv PATH /shared/local/texlive/2010/bin/`uname -i`-linux:$PATH

For bash, sh, zsh, or other Bourne/Korn shells:

export PATH="/shared/local/texlive/2010/bin/`uname -i`-linux:$PATH"

[uname -i will expand to the appropriate architecture for the machine you're logged into; either i386 (for 32-bit machines) or x86_64 (for 64-bit machines).]

For Macs, for the tcsh or csh:

setenv PATH /shared/local/texlive/2010/bin/universal-darwin:$PATH

For bash, sh, zsh, or other Bourne/Korn shells:

export PATH="/shared/local/texlive/2010/bin/universal-darwin:$PATH"

Note that setting your PATH in this way will not affect the PATH used by applications such as TeXShop, only the Terminal session in which you set it. You can set the path in the Engine tab of the TeXShop Preferences dialog, and reset your preferences to defaults using the drop-down menu in the bottom-left corner of that dialog. (Resetting your preferences using this method may change other preferences besides the paths-be sure to check.)

At about 6:30 this morning, the gigabit switch that provides connectivity to our server cluster died, causing loss of all server-related functionality, including web service (for the department, the ODE Toolkit site, the CODEE.org site, and mirror.hmc.edu). Also interrupted were file service, logins, and incoming and outgoing mail.

I found out about the problem at about 8:30 when Suzanne called me. With DruAnn and Roger's help we figured out that the switch had died; Roger tried to reboot it but the switch remained wedged. Service was restored at 10:21 AM after I replaced the switch with the switch from the Amber cluster, which will be offline until we have a more permanent solution.

I will be investigating our options for replacing the network switch and, I hope, adding some redundancy to our connectivity. More details as I know them.

From what I can tell, service should be restored to all workstations and for all services. If you experience any problems, please let me know ASAP.

Apple has finally announced the tablet computer that people have been begging for over the last few years. But what they've announced isn't exactly what everyone was hoping for-in particular, the iPad doesn't run Mac OS X, but a variant of the iPhone OS. So any iPhone apps you might currently use will run on the iPad, but you aren't going to be running Mathematica, Maple, MATLAB, SAGE, or any other serious math software on the iPad.

On the other hand, the iPad will have versions of Apple's iWork applications-Pages, Numbers, and, most importantly for teaching use, Keynote. And the iPad will support video output to VGA for connecting to projectors (at 1024 x 768 pixels resolution). From video taken by testers, it seems that the iPad version of Keynote will allow users to "draw" on their slides by drawing on the touchscreen with their fingertips. It's not clear at this time whether the iPad version of Keynote will support the presentation mode that you get on a laptop (where the projector/external monitor shows the slides and the laptop's screen shows notes, timing, previous or next slides, or other information).

For text input, the iPad has a on-screen keyboard similar to the keyboard on the iPhone or iPod touch; the keyboard pops up when you select a text-entry field by tapping on it. With the addition of serious word-processing software in the form of Pages, Apple has also decided to allow the use of an actual hardware keyboard, in the form of a special dock with an attached mini Apple keyboard or through the use of a Bluetooth keyboard. In the iPads provided for people at the announcement to try out, keyboard support isn't quite there, but we can presume that Apple will have things working by the time they actually ship.

There is a nice overview, with pictures of various apps, the iPad itself, and some of the accessories at iLounge.

Complaints

Until the iPad actually ships, it's hard to know exactly what it will and won't support-issues reported today with the samples may disappear by the time you can buy one. But there are some things that lots of people are complaining about that we can be pretty sure won't be addressed by the time the iPad reaches stores, and maybe never will be.

Flash

Apple doesn't support Adobe's Flash on the iPhone, and it doesn't look like they'll allow it on the iPad, either. (John Gruber sums up the reasons.) Overall, I'd say no Flash is a good thing-in my experience, Flash is used for three things: (1) embedded video, which can be provided using other formats and in more standards-compliant ways; (2) bits of text set in particular proprietary fonts; and (3) really obnoxious ads. It's also the case that Flash uses vast amounts of system resources, and still performs badly-if I try to watch a Flash video on my 2.4 GHz Core 2 Duo machine with 4 GB of RAM, I see stuttering, the machine heats up dramatically, and the fans begin to roar. If the iPad helps kill Flash for video, I'll be thrilled.

iPhone OS and the App Store

As the iPad runs a version of the iPhone OS, it won't run standard Mac OS X applications, only those built specifically for iPhone OS devices. Combine that limitation with the significant hurdles of developing for the iPhone platform (it costs money to be a developer; you need a Mac to do development; Apple's baroque and somewhat unpredictable vetting process), and it's unlikely that a lot of software that's available for free on other systems is going to appear on the iPad.

The positive spin here is that these devices have a radically different interaction model than traditional computers, and that forcing people to "think different" to develop for them seems to have resulted in some amazing applications that not only work well but might not even be possible on other platforms.

Lock-In and DRM

The Defective by Design campaign has pointed out that the digital-rights management (DRM) restrictions built into the iPhone/iPad platform are, in many ways, a threat to open standards and free software. By restricting the software that can be installed on the device to things that pass muster with Apple, Apple is limiting what iPad owners can do with the device they've paid for. There's also likely to be DRM limitations imposed on textbooks and video (as there is using the iTunes Music Store now).

These are complex issues, and ones that don't necessarily matter to most people until they actually find themselves running up against the limits that are in place. For many users, that will never happen, but some will chafe under the limitations.

On the positive side, Apple did fight the good fight with the music industry to eventually push them to support DRM-free music so that all the music Apple now sells in the iTunes Music Store is DRM free (although iTunes and iPods impose some limits on where music can be copied using their interfaces). We can imagine that they might do the same for video and book content.

It's also the case that most "content providers" are more interested in protecting their copyright interests than they are in moving into new markets. Thus providing some sort of DRM system is probably a requirement for getting them to make things available digitally in the first place.

No Handwriting Recognition

Many people were hoping the tablet might be a replacement for the Apple Newton, a handheld computing device that supported many of the functions the iPad does include, but also had a sophisticated handwriting-recognition system. Jobs killed the Newton shortly after returning to Apple, but hope has never died, and continued support for handwriting recognition in Mac OS X (with Ink) has allowed that hope to continue.

Instead, the iPad has what looks to be the same on-screen keyboard as the iPhone and iPod touch, but large enough that it can support touch typing, as well as support for hardware keyboards through a special dock and Bluetooth.

But we can continue to hope....

No Camera

People were really hoping for video chat, and there are various hints left in the OS that suggest that a camera may have been planned, but there was no camera in the versions available for testing.

No Background Apps

Like the iPhone, you get to run one application at a time unless the application takes advantage of the push notification API (or was written by Apple). So if you have a chat client with push, you can do something else and be notified when a new message comes in, and even listen to music at the same time using the bundled iPod app, but if you wanted to read a book and listen to music streamed through Pandora or a similar app, it sounds like you're currently out of luck.

Rumor is that iPhone OS 4.0 might (finally) include background apps, but we won't know for sure until it's released (maybe at the same time as the iPad itself).

Should You Buy One?

The big question, of course, is whether or not you should be interested in an iPad. The answer depends a lot on what you think you might want to do with it.

If you just want a device to watch video, surf the Web, play games, listen to music, and do casual e-mail, then the iPad might be a good choice for you, especially if you don't already have a laptop computer or an iPhone. (The iPad seems like it would be a very nice companion to a desktop machine for someone who doesn't need to do a lot of number crunching on-the-go.)

Similarly, if your class presentations use Keynote (or could use Keynote; note that PDF to Keynote allows you to convert PDF presentations, such as those created with TeX, to Keynote format), then the iPad might work well.

And if you want a device for taking notes, then the iPad might also be okay, so long as you can find an application that will let you do what you need (which might mean using a web-based tool, a note-taking app that stores files as text, or even Pages). If you're hoping to type LaTeX code, you're almost certainly going to want an external keyboard, as the on-screen keyboard makes getting to various punctuation characters used extensively in LaTeX painful.

There's also the promise of textbooks in ePUB format; depending on how pricing works out, it might be cheaper for students to have an iPad (with all the iPod functionality) and electronic textbooks, but I don't think we'll know until after publishers start making textbooks available.

My Take

I already have both a laptop and an iPhone. Most of what I do on computers involves typing shell commands into terminal windows, editing files (HTML, LaTeX, and other text formats) in Emacs, and web browsing. While I can imagine the iPad being nice for reading while walking (much nicer than trying the same thing with a heavy laptop), the number of times that I might want to do such a thing where my iPhone can't cover my needs are few (and the iPad still weighs 1.5 pounds, which is a lot if you're carrying it around with an extended arm). So, for me, I can't quite see the point-I'll be waiting to see what happens a couple of generations down the line. There are some very interesting new user-interface elements and interaction paradigms in use with the iPad that may well feed back into other computing platforms, even desktops or traditional laptops. And it's possible-likely, even-that we'll see additional functionality appear in later versions of the iPad that might make it more attractive to users like me. (In particular, I would like to see handwriting recognition; with that feature, we could see a whole renaissance in handwriting skills!)

There will be a power outage affecting all of the Claremont Colleges campus over the break. The outage is scheduled to begin on December 26, and to end as early as December 31; given that previous outages have been extended several additional days, I would expect to see something similar this time.

Lights, heat, and all power except for limited areas will be turned off throughout all the campuses, but the colleges and departments will provide some Internet-accessible computing services during the outage.

Here's the service breakdown for the mathematics department:

Available

Mail

Incoming (IMAP, POP) and outgoing (SMTP).

Web

All web services will continue to be available.

Shell

During the outage, ponder will remain available for shell access.

Mirror

mirror.hmc.edu will be available.

Not Available

Desktop and Lab Machines

Office, Clinic, and Scientific-Computing Lab machines will be offline.

The shell.math.hmc.edu alias to the SciCompLab machines will be unavailable.

High-Performance Computing

hex and the Amber cluster will be offline.

Subversion/Updates

vetinari and yum will not be available.

Printing

All printers will be offline.

I expect that we will get most of the systems that we take down back on line within a day or after I'm sure the power system is stable. If there are particular services that you'll need over break that you'd like prioritized, please let me know.

I may have more information as the time for the outage gets closer, as well as during the outage itself. I will post longer messages to this blog; shorter notifications may come via the hmcmathcomp Twitter stream.

TeX Live 2009, a complete TeX system for use on Linux, Mac OS X, and Windows, has been released!

This release contains the latest versions of the various TeX binaries, as well as a wide variety of LaTeX packages, fonts, and other support files. Major new features include the cross-platform TeXworks editor, modeled on the TeXshop editor on Mac OS X; and new versions of the AMS PostScript Type 1 fonts, including the Computer Modern family, and an updated set of Euler fonts incorporating new designs from Hermann Zapf.

We currently have TeX Live 2009 installed on our Linux systems, but not as the primary TeX system; using it requires you to add /shared/local/texlive/2009/bin/i386-linux (on ponder) or /shared/local/texlive/2009/bin/x86_64-linux (on the other Linux systems) to your path. TeX Live 2009 will become the default TeX system on the Linux machines in the near future (once it has propagated to more mirrors).

TeX Live 2009 is available on our mirror server from http://mirror.hmc.edu/ctan/systems/texlive/. There are DVD ISO images that can be downloaded (in the Images directory) as well as a network installable version (in the tlnet directory).

For Mac OS X users, the MacTeX-2009 package should be available soon from our mirror server, in http://mirror.hmc.edu/ctan/systems/mac/mactex/. (Note that the mactex-20090320* packages are not the new release; the new release, with a date similar to 20091108 should appear soon.

Current versions of PDFTeX resulted in problems with the PDFTeX-detection code in the hmcpset homework LaTeX class, making it unusable.

A new release of the hmcpset class, 0.5, addresses this issue by substituting the use of the ifpdf package for the offending code. That version is now the current version for users of the department's Linux cluster and is available for download from the class's support page, at http://www.math.hmc.edu/computing/support/tex/classes/hmcpset/.

As the older version of the class is unusable with current TeX systems (e.g., TeX Live 2008 or TeX Live 2009), we encourage users to download the newer version as soon as possible.

As usual, please report problems to system@math.hmc.edu.

We've changed the combination for the door to the Scientific Computing Lab. Anyone with an account can find out the new combination by logging into a department machine and reading the contents of the file /shared/local/scicomp-combo.

We will be taking the entire Scientific Computing Lab offline for a few days. During this outage all of the machines in the lab will be rebuilt with a generic OS install in preparation for replacement. We will then pull the machines out and make them available for scavenging in the hall behind Big Beckman.

With the machines out of the lab, we will have the room cleaned thoroughly, and then we will install the new machines in preparation for the fall, 2009, semester.

The exact dates for this outage have not yet been determined, but early during the week of August 10-14 is the likely target for decommissioning, with the new machines being installed later that week or during the next week.

Stay tuned for more news, or check our Twitter feed!