Math (LaTeX) support on Blogger

Blogger can support LaTEX-style math, if you install a couple of scripts as a cross-column gadget. Here's the scripts running now (the inline math seems a bit finicky!):

<script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>

<script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>

Some instructions from MathJax here: https://www.mathjax.org/#gettingstarted.

A standalone equation (even if it's inline in the source): $$e^{i \omicron} = ?$$

And a couple more standalone equations:

$$e^{i \pi} = -1$$

\[e^{i \gamma} = ?\]

An inline equation (seems a bit finicky): \(\gamma\) and \(e^{i\pi} = -1\)

$$e^{i \pi} = -1$$

$$e^{i \pi} = -1$$

If you really want inline equations, you can probably add the MathJax JavaScript module and a slightly different syntax to include math. For details, Google inline equations blogger mathjax or something similar.

Android Home Screen: Samsung Galaxy S (Fascinate)

Update: I'm retaining this post for historical interest only (I suspect no one still has a Samsung Galaxy S anymore). Also, I've removed the screenshots since they seem to be broken now -- not sure if this is a Blogger problem.

My daughter and I just got the Samsung Galaxy S phone running the Android operating system.  We are trying to figure out some basic customization operations. 


One of the first things we wanted to do was to get rid of some of the screens and icons that initially clutter the interface (especially because we didn't choose them).

Setting the home screen

• Go to the home screen by tapping the home icon at the bottom of the phone.
• Tap the menu icon at the bottom left of the phone. The menu will pop up at the bottom:

Home screen menu

• Tap the Edit page item. Images of all your home screens will appear (initially you may have six or seven home screens set up by your service provider):

• Click the Set home bar on the screen you want to be the home screen.  Or click the + screen to add a new blank screen that you can customize. You can use a blank home screen to add only the apps that you really use. Your new home screen will appear whenever you tap the home icon.

Removing screens

You can also remove excess home screens. Press and hold the screen you want to remove, then drag it to the Remove trash can at the bottom of the screen:

Cloud Computing and Storage

For the last few years, I've worked at a company (Desktone, Inc.) that provides virtual desktops as a service. Now, virtual servers have been around for some time, but virtual desktops are just starting to catch on.  Having used a virtual desktop for the last three years, I can say that it's been a great experience.  I used to bring my laptop home with me every night on other jobs.  But at Desktone, except for the first couple of weeks (before I broke the habit), I never brought my laptop home with me, because I could always access my virtual desktop from home, or from my mom's house, or wherever I happened to be.  My desktop was in the cloud, and as long as I had Internet access, I could reach my desktop (and my data).

Some things about computing you don't learn until you don't have them.  For example, when the network goes down, you realize how important it is to your work.  No network, no connection to web sites, Google, blogs, or your virtual machine. I used to assume that the machine itself was important too.  But with a virtual desktop, there's no physical box -- no desktop or laptop to lug around (even though your virtual desktop does live somewhere on a real server in a data center).  I did not miss the physical machine one bit.

The other important element of personal computing is storage.  Where's my stuff?  With a virtual machine, my data could be on the local disk (C: drive) of the virtual desktop, or it could be on a network share of some sort, mapped to My Documents (yes, we're talking Windows desktops here, but this could apply to any OS). Or, my data could really be in the cloud, on a disk or storage system somewhere far from the virtual desktop.

There are a number of companies that market services for cloud storage or backup.  The best I've come across so far is Dropbox. Dropbox gives you 2GB of storage for free, and you can download a client for Windows or Linux systems (I have not tried it yet on my Ubuntu systems Update: I installed the Ubuntu Dropbox client, and it works great).  The great thing about Dropbox is that it shows up as a folder (directory) in your file system.  So you can have it under My Documents or /home/user or wherever, and when you save a file there, it saves it on your local machine and also in the cloud.  But the best thing about Dropbox is that it synchronizes the files in your dropbox to any other machine that has mounted that dropbox. No more emailing files to yourself or using USB zip drives to transfer files.

I think that storage is going to be the big story in cloud computing, because user data is the most important thing to individuals and companies.  Whether it's photographs, music, and videos, or spreadsheets, databases, and Power Point presentations, it's the data that defines.  Whoever can come up with a cloud storage solution that is secure, simple, and inexpensive will have a strong business as data storage needs grow rapidly.

Update (9/29/2011): Since I originally wrote this post, Dropbox did have an incident where they left open access to storage accounts. Keep in mind that no matter how much you trust your cloud storage provider, you data is on their disk drives. For most of us, this is probably more secure than it is on our own drives, but it is an important consideration.

Reinstalling Windows

My daughter's laptop slowed to a crawl last week. Despite up-to-date antivirus and anti-spyware software, something (or things) worked to make it unusable. I knew that we had reached the point where we needed to reinstall Windows.  I had not done this since back in the Windows 3.1 days, when it seemed like you needed to reinstall once every month or so. But Windows Vista is huge, and there are so many more devices and applications. So I checked out Leo Notenboom's site http://ask-leo.com/ for advice. Leo has lots of great posts on all things technical, but especially directed at home users who may not have an extensive IT background. If you listen to Leo, you'll have fewer problems with your computers in the long run. Unfortunately, we have not been heeding most of Leo's advice.


So the first thing we did wrong was not having recent backups.  We do have a portable hard drive, but our backup schedule is sketchy at best. The computer running Windows was so slow as to be unusable, so we could not use it to do a backup.


Luckily, we were able to boot the computer into safe mode with a DOS command line only. Annie was fascinated to find out that the command line even exists. I struggled for a few minutes to copy her data to the portable hard drive using the copy command, cursing it for not having a recursive option (why can't DOS be like Unix?).  Then we googled "recursive copy dos" and became reacquainted with the xcopy command.  We used xcopy to copy all of Annie's current data to the portable drive.


Then, using the OS reinstall CD that came with her laptop, we were able to reinstall Windows Vista.  That part was easy.  But the driver reinstall CD was not easy to navigate.  We finally found an application on that CD that allowed us to reinstall audio, video, and communication drivers that matched the hardware installed on the laptop, so we could use the highest screen resolution and get out to the Internet.


First thing we did was to install the latest version of AVG antivirus (the free version) and get that up and running. Then we ran Windows Update (71 updates since the laptop install of Windows).  Then we installed Firefox and Microsoft Office and a few other applications.


The laptop is running smoothly and quickly now, and we've learned a bit about backing up from the DOS command line and building up a machine from scratch (well, not completely from scratch, but close enough).