Category Archives: Technology

Merge Multiple Contacts in Gmail

An awesome new feature was recently announced by Google for the contact management tools in Gmail.  If you have multiple contact entries for the same individual in Gmail you can now easily merge them into one.


(From Lifehacker)

For example, if you’re staring in the face of numerous duplicate contacts that should represent the same person, the built-in contact merge feature in Google Contacts is a must. Just find the duplicate contacts, tick their checkboxes, and click "Merge these contacts…." Easy peasy. To manage your contacts, either head to the Contacts page in Gmail or to the unadvertised standalone site.

Gmail just keeps getting better.  I was back to using Outlook for long while until the Tasks feature was launched.  Now, all my email addresses are dumped into Gmail.  I don’t think I’m going back.

Oh, and thanks to the IMAP capabilities in Gmail, I have uploaded all my archived email into my Gmail account.  I can search my work emails dating all the way 2002. 

Oh, and I love the new Multiple Inboxes feature, as well.

Oh, and how about those themes?

You’ll find nothing but love for Google here…

How to not lose face on Facebook

image Be careful what you say.  You MUST assume EVERYONE is listening.

Every semester, I try to remember to convey this idea to my students in each of my classes.  Those that use online social networking tools like Facebook, MySpace, LinkedIn, Twitter, etc., must assume that when they put themselves out there, no matter where it is, anyone can see it.  I understand that most of them require you allowing people to view your page and follow your status updates, but there is very little guarantee that your information is going to be kept confidential.

I tell them to think of it this way: Imagine that you are applying for a position or even a promotion down the road.  Your boss sits down to a computer and “googles” your name.  What will they find about you and how will that affect their decision to hire or promote you?

As for a professor who also uses these tools, I have to be very careful.  I’ve set a policy for my blog that I will NOT discuss details about students in my current classes.  And later on, if I do decide to discuss specific students, I will NOT mention any incriminating information (without their full permission).

I was forwarded an interesting article regarding this very issue this morning (HT: Jay S.).  It is from the current issue of The Chronicle of Higher Education and it is entitled, “How to Not Lose Face On Facebook, for Professors” by Jeffrey R. Young.

He makes some of the same points in this article but goes on say:

But Facebook, like e-mail, yields more pros than cons, so the trick is to learn to master it rather than ignore it. That’s according to Nicole B. Ellison, an assistant professor at Michigan State University, who spent the past three years researching student behavior on Facebook, and who uses it herself. "There’s tremendous potential with these social networks for developing relationships and being exposed to different perspectives," she says. They are particularly well suited to academic work, where researchers need to keep up with a number of far-flung colleagues.

I totally agree with this and have been absolutely blown away by my ability to keep up with our past graduates plus finding alums from years gone by.  It is an amazing tool for connecting with people.  And no, I haven’t begun soliciting donations from them just yet but you never know.

On a related note, I still a little creeped out by the idea of a professor, like me, requesting connection (“Adding as a friend”) from my current students.  If they request it from me, no problem, but the other way around just seems inappropriate.  Plus, the Provost of our University is on Facebook and I have yet to request his friendship on there just because I don’t necessarily want him to know that I’m updating my status 4 or 5 times a day during work hours.

What boundaries have you set or would you set on a professor using social networks like Facebook?

I take it back!

image So far since the beginning of the week , I have received no less than four messages claiming to have attachments that did not.  Within seconds of receiving them, a follow-up email arrives confessing the stupidity, idiocy, or moron-itude of the sender plus the previously promised attachment.  I point no fingers as I am as guilty in this matter as anyone else.

Worse yet are those “Reply-to-all” instead of “Reply” mistakes.  Even worse is the Reply instead of Forward to.  I recall one time receiving an answer to a question from the Facilities Manager here on campus (my land-lord, basically) which I did not like.  Instead of forwarding to my wife my response of “Ugh!”, I replied that back to him.  Nice move, Einstein.

So, here’s a recommendation to all you happy clickers that let the send button do the talking when you’re not quite ready:

Email Delivery Delay in Outlook 2003/2007:

This allows you to double check and re-think sending your email even after hitting the send button.  It causes your email be held for a specified number of minutes after hitting send.

  1. On the Tools menu, click Rules and Alerts, and then click New Rule.
  2. Select Start from a blank rule.
  3. In the Step 1: Select when messages should be checked box, click Check messages after sending, and then click Next.
  4. In the Step 1: Select condition(s) list, select any options you want, and then click Next.

    If you do not select any check boxes, a confirmation dialog box appears. Clicking Yes applies this rule to all messages you send.

  5. In the Step 1: Select action(s) list, select defer delivery by a number of minutes. Delivery can be delayed up to two hours.
  6. In the Step 2: Edit the rule description (click on an underlined value) box, click the underlined phrase a number of and enter the number of minutes you want messages held before sending.
  7. Click OK, and then click Next.
  8. Select any exceptions, and then click Next.
  9. In the Step 1: Specify a name for this rule box, type a name for the rule.
  10. Click Finish.

Forgotten Attachment Detector in Gmail

For Gmail there is an experimental feature that detects from the wording of your message that you intended to attach a file but did not.  It pops up a warning if it thinks you meant to attach something.

To enable this feature, go under the Google Labs section of the Settings page in Gmail.  Scroll down to “Forgotten Attachment Detector” and select Enable.  Then click “Save Changes” at the bottom.

I just turned it on for the first time and ran a few tests on the way I might say that I have an attachment.  For example:

  • I have attached a file” – works
  • see attached” – works
  • see attachment”- works
  • “Attachment” as subject line – did not work
  • Here is the file I mentioned” – did not work

Not bad.  It’s worth having running in the background.

Mail Goggles in Gmail

For those emails that you send late in the evening or over the weekend when your head isn’t in the right mindset to respond to some naysayer at work, wouldn’t be nice of something stopped before you vented all over them.  How about having to work out 5 arithmetic problems before you send? That would give you time to reconsider what you have written.

There’s another experimental feature in Gmail that does just that called Mail Goggles.  I don’t use this one but I’ve played with it.  You can control the difficulty and set a schedule for when this will interrupt your sending.


I have yet to discover a way to delay the delivery of an email sent through the Gmail web interface.  If anyone knows how, I’m certainly interested.





Twitter summaries are history

imageJust a short post here to let you know that I am discontinuing the “Twitter Updates of the Week”.  For the last few weeks, I have had a plug-in for this blog post all of my Twitter posts, aka “tweets”, for the previous week.  Since I have Twitter piped into my facebook status, most of the friend of this blog were getting a double or even triple dose.  I felt it cluttered up the blog and misrepresented the blog’s primary purpose.  So, they’re history.

If you’re interested in keeping up with the life and trials of the Christian Mathematician, you can follow me on Twitter ( or you can just take a gander to the right of this post in the sidebar where you’ll see my latest status update.

By its very nature, this blog is a work in progress.  What I intend for it to be changes from week to week.  There are spurts of activity and the lulls.  I appreciate those who continue to follow and I hope that every once in a while something of interest tickles your fancy, as they say.

Shortest Sudoku Solver in Python

image Well over two years ago on this blog (have I really been around that long?), I posted a link to a story that Sudoku had been solved.  (The original link to the Math-Forge Story is broken, so here in alternative version of the story.) While just about every computer scientist and programmer I know has thought up a quick little code to solve a Sudoku puzzle, the interesting element of the above story is that the algorithm solving Sudoku was connected to techniques used in diffraction microscopy.

Now, when I say “quick little code”, I meant an easy algorithm to implement, but not necessarily an elegant or amazingly small code that would accomplish the solution.  Here is definitely the smallest (shortest) code I’ve seen that will do it.

def r(a):i=a.find('0');~i or exit(a);[m
in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for
j in range(81)]or r(a[:i]+m+a[i+1:])for m in'%d'%5**18]
from sys import*;r(argv[1])

Here’s one that is slightly longer (185 bytes as opposed to the 178 above)

use integer;sub R{for$i(grep!$A[$_],@x=0..80){
R($A[$i]=$_)for grep!$t{$_},1..9;return$A[$i]=0}

HT: Scott’s Blog

Conducting an online mathematics course

I gave a presentation today to my colleagues at WBU in order to train them on teaching an online mathematics course.  We have offered College Algebra online for the last year and, so far, I have been the sole instructor.  I developed a series of lecture videos and notes for the students.  We are now ready to have additional instructors leading the course that was developed.

For your own edification, I have posted the presentation to AuthorStream.  I’m certainly open to any questions or critiques you may have regarding our system.
Uploaded on authorSTREAM by splineguy

Forest Fire Simulation in MATLAB

In my Fall course of Math Models, I have three groups working on projects to finish up the semester.  One of the groups have an assignment to explore a model of the spread of a forest fire.  The assumptions are that the trees are on a rectangular grid, or a lattice.  The time is a discrete variable and at each time step the probability that the fire spreads from one point in the lattice to an adjacent point (up, down, left or right) is given by p.  For simplicity, the event that the fire spreads to each point is assumed to be independent of any other point.

Part of their project is to implement a numerical simulation of their forest fire.  I couldn’t let them have all the fun, so below is an example of my version of the simulation in MATLAB.  I have to hold off on posting the code until after they have handed in their project.

In the graphical representation of my simulation, green represents an unburnt tree, black is burnt and red is currently on fire.  The fire lasts for exactly one time step.  I also implemented a 3-D version, where a height of 1 is unburnt, 2 is on fire, and 0 is burnt.  I’ll confess to having way too much fun with this.

I have used a 200×200 lattice with p = 0.5.

Update (3/4/16)
I promised a LONG time ago that I would post the code.  I finally got around to it.  Here are links to the m files that were used to generate the graphical simulations above: