Sunday, January 31, 2010

SHADOWFAX: Many miles left to go! (setting up openMPI clusters)

OK, nobody said it would be easy!  Whoever said "instant super computer, just add water" when referring to setting up an openMPI cluster over a LAN of 25 multi core 64-bit nodes was nuts.  Oh, yeah, that was me...

How about a little bit of history?  CIS(theta), the Computing Independent  Study class, has been around in one incarnation or another for over a decade:

2009-2010 SHADOWFAX openMPI cluster with dual core 64-bit AMD 2 GHz Athlons (work in progress).  We are trying to emulate pelicanHPC ( on a Linux Partition.  We based this cluster on the Fedora 11 CD 64-bit Linux distribution and gigaE (gigabit Ethernet).

2008-2009 CISTHETA public key authentication cluster with dual core 64-bit AMD 2 GHz Athlons (used bash scripts to scatter/gather jobs on new architecture).  We did some nice ray tracings using povray (  We based this cluster on the KNOPPIX DVD 32-bit Linux distribution and fastE (100 megabit Ethernet).

1997-2007 CENTAURI openMOSIX cluster with various Pentium class processors (modified load balancing Linux Kernel that automatically sent jobs to other nodes whenever a node was overworked).  We also dabbled with Beowulf, PVM and MPI.  We based this cluster primarily on cluster KNOPPIX (, QUANTIAN ( and BCCD ( and basE (10 megabit Ethernet). For the last few years, we installed the QUANTIAN DVD to a Linux Partition and used a dual boot lab (with WimpDoze).  We did some nice fractals with the fork() method of g++ (

The main difference between CISTHETA and SHADOWFAX is twofold. Last year, CISTHETA did not implement any clustering environment like MPI.  We simply broke up our jobs into slices and sent and recieved results using bash scripts.  Another main difference was that we set up public key authenticated ssh clients such that you could login as "cluster" on any node, and be automagically logged into all nodes.  In fact, you could ssh to any node with or without the userid (cluster) and you did not need a passwd.  Lets call that "static public key authenticated ssh."  The static method is set up once and used many times.  This year we are using something I'll call "dynamic public key authenticated ssh," such that the RSA keys are generated on the fly.  Under both schemes, the user could start a parallel job from any node making that node the master node and control any number of other nodes as workers.

What's frustrating about all this, is that most of the clustering software we've tried seem to work great "right out of the box" on any one multi core node.  In other words, SMP works by default, but extending the parallel jobs over a cluster of such nodes is a production!  These clustering packages are as follows:

parallelPython: &
dSAGE: and

We've gotten openMPI's Torque severs to work with gcc.  However, the Linux distro we based our new cluster on this year was the Fedora 11 CD 64-bit version.  I think we may need to start over with the Fedora 12 DVD 64-bit Linux distribution so as to include g++ as well.  We may all need to re implement "static public key authenticated ssh" which worked very well last year....

Happy Clustering,

Friday, January 29, 2010

ROOM429: Giving Thanx! (thank you package at

Oh boy, if you haven't heard about you really owe it yourself, and your students, to check out this website yesterday and jump on this band wagon now! Here's my site,

This is a site whereby a teacher can ask for donations by writing an ad describing what they need for their classroom.  People can then peruse the various listings and decide if they want to contribute the full cost of the project or any fraction thereof.  I recently got a new PC Projector for my PC Classroom this way. Here's a blog about my project!

All I had to do afterward is an online thank you package.  Now I get more points to spend on a new project!  When you first sign up, I think you get 3 points.  After you spend points (worth about $200 each in their online catalogue) you can earn them back by completing the thank you package.  The picture you see above is one of many that I took for the thank you package. 

Here's a sample thank you letter one of my students wrote:

Dear XXXX,
Thank you so much for making it possible for our class to learn Calculus to the best of our ability.  The projector is an essential tool in our classroom because without it, we'd have to squint around our teacher as he furiously scribbled on the blackboard, and if we didn't copy down every detail of what he was writing, it would be erased forever!  With the projector, our teacher is able to use Smart Notebook to write notes that are projected on a large screen at the front of the classroom, so that even the students in the back can clearly see the large numbers, letters and graphs.  Everything that we see on the screen and hear coming out of the teacher's mouth is recorded onto a website where we can go back and re-watch each lesson for review.  Clips that are about 10 minutes long from each lesson are posted on You Tube so that studying for tests is easier and more concise.  The notes that are projected during class never have to be erased because they are saved on a website that enables us to print them out even if we miss class.  The projector enriches our Calculus experience and makes it immeasurably more convenient to study for this notoriously difficult subject.  I know I speak for every student in the class when I say, "I can't imagine Calculus class without the wonderful projector you have so generously helped us obtain."

Learning with Technology,

Thursday, January 28, 2010

COMPUTING: TI BASIC was a huge success! (teaching BASIC in today's PC classroom)

First, I showed all those videos on programming the TI-83/84.

Then, I installed VTI on my Fedora 11 CD clients using wine. 

So, we wrote some simple IPO (input, process, output) programs (eg: input 3 sides of a triangle a,b,c and process the area with heron's formula and output the answer).  

We also wrote some looping apps (ie: enter a number of grades to average).  
Finally, we wrote a quadratic equation solver that used conditional statements to output the nature of the roots as well as the roots themselves in a+bi form.  
For a week and half final project for a semester intro course, I think it went quite well.

BTW, I misspoke in my last posting on this subject. I said there were a number of good sample programming videos on youtube for the TI-83/84. I also said, mistakenly, that there were no such good videos for the TI-89. Well, see the video for yourself as its embedded above. I don't know how I missed it as its one of my own recordings! 

Teaching with Technology, 

Monday, January 25, 2010

SAGE: Taking the show on the road! (up coming conferences and art shows)

I have several conference talks and art shows coming up: ICON 3/26/2010 Art Show & Print Shop (Science Fact & Fiction at SUNY Stony Brook)
LIMACON 4/16/2010 "Look Ma, No Calculator" (Long Island MAth CONference at SUNY Old Westbury)
PI DAY 4/17/2010 Art Show (at Suffolk County Community College Grant Campus)
T^3 11/5/2010 "Look Ma, No Calculator" (Teachers Teaching with Technology at Molloy College)
The conference talks will be based on a presentation I gave earlier this year at a Staff Development Day at my school: "Look Ma, No Calculator!"  In this presentation I'll compare and contrast how I use a TI-83/84 vs how I use SAGE in math class (see summary below).  For example, take a look at session #47.  I will also discuss my youtube channel and how I record my lessons.
The art shows will showcase the digital art prints (fractals, ray tracings, etc) my students created on our cluster, SHADOWFAX. Take a look at for the fractals and for the ray traced scenes.

"Look Ma, No Calculator" summary:  This will be a "Show & Tell" session where I show you how I teach math using technology without ever touching a calculator!  In Part I, I'll show you the old fashioned way using a TI-83/84 Graphing Calculator (or the TI-89/92 if there's interest).  If you have your own TI Graphing Calculator, please use it to follow along!  But that's SO last century...  So, in Part II, I'll show you how we do things in my classroom now-a-days using SAGE, a Computer Algebra System!  I'll leave it up to you to pick and choose any techniques you think you may want to use in your classroom.
PART I: I will record a math lesson on something simple like solving quadratic equations with a program (see  I will use Smart Recorder or Screencast-o-Matic + Smart Notebook + VTI to render the class recording as a wmv or mp4 file for uploading to my FTP site or YouTube. (30 min)  
PART II: Then we'll reboot all the PCs in Linux with the SAGE CD and show how the same lesson can be done with a Computer Algebra System.  You can follow along using your own PC! (30 min)  
PART III: In summation, I'll share my website, blog, and youtube channel, as well as my zazzle and deviantart digital art galleries.  I will also show everyone how to use with any Mozilla clone so they won't even need a SAGE CD. (15 min)  
PARTY FAVORS: Everyone goes home with my URLs (see business card below) and their very own copy of SAGE (on a live linuxCD)!

Generally speaking,

Sunday, January 17, 2010

COMPUTING: Youtube Wednesdays still going strong! (teaching TI-83 BASIC)

I have a Computer Math class every Fall semester and an Advanced Computer Math class every Spring.  This is an introductory year for learning how to program, look at some algorithms and start a little Scientific Computing.  In the Fall, we use yabasic ( in Linux which is a lot like the old IBM BASICA and MS QBASIC.  We sometimes use MS VB6 or REALbasic (  In the Spring, we play around with a little C++. 
I like to do a final project the last 2 weeks or so of each semester that’s a little different each year.  This year, I installed WINE on our Fedora clients and installed VTI, the Virtual TI graphing calculator emulator.  So, I’m thinking of using what my students learned about yabasic to program a TI-83 at the end of this semester.  Then, I’d like to use what they learned about C++ to program a TI-89.

Take a look at the youtubes I embedded above with this article.  I showed one two weeks ago to wet my students’ appetite.  I showed the quadratic equation one this past week.  We’re going to write programs like these next week on our TI-83 emulators!  Unfortuantely, there aren’t any good youtubes on programming a TI-89.  As luck would have it, I can use my best seller on EBay:

Teaching with Technology,

COMPUTING: Does this happen to you? (my legend precedes me)

OK, I’ve been teaching people how to program since 1975.  I’ve been teaching AP Computer Science since 1988.  I’ve been installing and maintaining LANs and Clusters since 1993.  So, I suppose my legend precedes me….
What am I talking about?  Well, whenever someone’s mouse isn’t working or monitor starts acting funny or they can’t login or save their work, “all I have to do is touch it!”  I put that in quotes because my students always say it.  If a student’s program won’t compile, sometimes all I have to do is walk by and it suddenly works.

Case in point, my brother-in-law has finally entered the 21st century.  He broke down and got a wireless Gateway laptop from and enabled his wireless router from Verizon.  He was surfing over to every day, happy as a clam, until the mouse stopped working.  Needless to say, hours of tech support from India was not very helpful.  So, he was incredulous when my own children said, “all he has to do is touch it!”  He didn’t want anyone to touch the laptop lest it break even more.  He was about to return the laptop to HSN when he let me touch it!  Guess what, I literally touched a button on the top of the display and all was well with the world once more.

Generally speaking,

Thanx! (using donors to get equipment for my PC Classroom)

I finally have a brand new Sharp XR-32X Multimedia DLP XGA Projector that produces 2500 lumens with a 2200:1 contrast ratio.  Thank God, we can now view my Smart Notes without going blind. Here's my donor site,
This is all thanx to where I posted last year that I needed a new projector for all my Smart Board and YouTube work.  Two kind donors surfaced during the summer and funded the project. I confirmed the order in September, but the original item was out of stock.  I ordered the Sharp projector and got it in October.  However, its been sitting in a box until now as we didn’t have the right ceiling mount.  So, thanx also go to the Tech Dept for finally making me a decent mount!

I will be completing an online thank you packet this week on which involves my students writing thank you letters to the donors and my taking pictures of them using the projector with my Smart Airliner Slate.  I also have to get permission slips from the parents to display these pictures on their site.  Once this packet is complete, I get more points enabling me to ask for more funding!

Learning with Technology,

SHADOWFAX: Meeting VII postponed due to make up week (trials and tribulations of using openMPI and g++ on a Fedora based cluster)

Today's Aim: g++, where fore art thou, g++?
Tonight's Reading: Building Parallel Programs, Chapter 7
This Week's Research: installing g++
Attending Thurs: JeremyA, SteveB, DevinB
This Thursday we will take stock of what we've done and what needs to be done.  For example, we got a Hello World program (hello.c) working over our Fedora based cluster using openMPI and gcc.  This is a great accomplishment!
However, when we tried to do this with C++ ( we found that g++ was not installed!  I did not realize that the 64-bit Fedora 11 CD we used for installation had GNU GCC with only gcc installed.  Usually, GNU GCC has gcc, g++, gf77, etc.  A lot of room on the CD is taken up with GNOME and Compiz.  So, we tried to yum install gcc but found the mirrors were down or missing or blocked???

Happy Clustering,

Saturday, January 9, 2010

SAGE: Breaking up is hard to do! (No Calculus Research Lab this year...)

I'm trying to drum up some interest for my new Calculus Research Lab (CRL), aka Scientific Computing Lab with SAGE to enhance the understanding and retention of AP Calculus.  We tried to get a section, starting in September, to meet every other day complementing the Calculus classes (AB & BC) that meet every day but we had an epic fail re scheduling.  The course was approved way too late last year for guidance to schedule the students properly. 
So, I thought I'd ask the current Calculus students to add CRL (meeting everyday) to their schedule now, for the Spring semester only, after Midterms Week.  There seems to be plenty of interest, but these students' schedules are already jammed!  The PC Classroom is only available periods 2, 3 and 5.  Luckily, I'm "off" those periods too, but too few students are (I'm never off as I do research and linux tech support when I'm "off").  I need a section of at least 10 students or the powers-that-be will not reschedule it.  I looked at the schedules of all my Calculus BC students (I don't teach the AB section) and found a lot had Lunch or Gym 5th period.  I thought there would be some flexibility there.  I suppose these students don't want to give up lunch.  

Well, neither do I....

Maybe I should be more like one of my heroes who said:  "do first, ask later!" Of course, that was Grace Murray Hopper.  In other words, I could start teaching these topics in other classes and sneak it in that way?  This is exactly how I got Linux in my school. I just decided to install it one day (1995?) and acted all apologetic when they told me I wasn't supposed to do it. By then it had been so entrenched in my AP CompSci curriculum  that they couldn't get rid of it! Of course, the powers-that-be had all kinds of arguments against Linux:
(1) "isn't it copyrighted?" no it's copylefted,
(2) "isn't it expensive?" no it's FLOSS,
(3) "what about tech support?" you're looking a him..... 

I have a "Computing Independent Study" class that meets once a week after school where we are playing with Clusters. We also do research on using various scientific computing environments (SAGE, Octave, R) in a PC Classroom setting.  Hence the approval to run a "Calculus Research Lab".  Maybe we could start these topics there?

I still have to use a GC in AP Calculus, but I can't say I'm happy about it.  However, I was in at the beginning of the Calculus Reform movement and the Rule of Four (GNAW every problem: solving Graphically, Numerically, Analytically and Wordily) in the early 90s. GCs were the only game in town back then.  BTW, I'm convinced that the low res LCDs in these GCs without color or back lighting that I used a lot for many years contributed to my needing reading glasses now....

Its really hard to pitch this sort of course when everyone else is using GCs, especially if the school has a large investment in class sets of GCs as my school has. Its even harder if you have TI-89s with CAS already.  I say, TI-83s and some Scientific Programming is great in math class, even a TI-89 and some CAS in Calculus is fine. However, take a look what we can do with SAGE in the PC Classroom.  Its like night and day, the GCs look like toys!

I made this exact arguement at our last Superintendant's Day (Election Day in November) where I volunteered to give a presentation entitled: "Look Ma, No Calculator!"  My supervisor loved it!  That's partly why I have a new course approval for a "Calculus Research Lab."  Now I just have to get some enrollment....

BTW, I'm giving a similar talk at LIMACON at SUNY Old Westbury (4/16/2010) if anyone's interested.  I also will be showing how I record all my lessons for YouTube using a wireles mic and PC Tablet (a lot like a SmartBoard).

Also, I think I'll give this presentation at the next T^3 (Teachers Teaching with Tecnology) at Molloy College in Rockville Centre (11/2010).  Do you think TI will be upset?  You see, TI is the main sponsor of T^3, so I don't know if they will appreciate a talk entitled "Look Ma, No Calculator!"  To be fair, the speaker invitation I received from Molloy just yesterday said I could talk about SmartBoards. Also, I do use a TI emulator (VTI) on my PC desktop. 

Teaching with Technology, 

ROOM429: A Little PC Classroom Remodeling after XMAS Break! (The optimal PC Classroom setup)

OK, I finally broke down and moved my whole room around ... again! 
I moved the front two rows about one foot forward.  Also, I staggered the back row so as to make room in the rear center part of the room for a Teacher Station.  Take a look at the pixs below!  Its almost a PC Podium/SmartBoard setup now.  All I need for a PC Podium is some extra audio/video/internet cables to easily hook up a laptop.  In addition, I wouldn't mind another PC in the Teacher Center so I can have one running WIndows all day and the other Linux.
(***)(***)(***)(***)          (***)(***)(***)(***)
(***)(***)(***)(***)     P   (***)(***)(***)(***)
                         (***)          (***)
        (***)(***)                           (***)(***)
(***)                                                            (***)
(***) = student "wooden" plus "pc" desktops (3ft)
TTTTT = teacher desktops (5ft)
P = ceiling mounted projector
M = marker boards
S = projector screen

Learning with Technology,

Friday, January 1, 2010

Merry Calculus & Happy Newton's Day!

Merry Christmas

and Happy

New Year 2010!!!

Don't forget that Sir Isaac Newton himself was born on Christmas Day.  So, I'm still celebrating the 12 Days of Calculus.  In fact, the 12th Day of Calculus is January 5th.   Hopefully, my students will have an Epiphany by then and finally understand U-Substitutution!
My favorite Xmas gifts this year were all the latest Paul Nahin books with MATLAB code in them! These books will come in handy as I have my Computing Independent Study kids, CIS(theta), setting up an openMPI Linux Cluster using Sage, Octave & R to solve problems in Applied Math and Physics - ie: Scientific Computing.  
NEW YEAR'S RESOLUTION: My final project this year after the AP Calculus exam will be to investigate some of the problems from Nahin's Digital Dice using Octave.  Further, I resolve to use Sage and Octave more in class!
I also got a DVDR with dual VCR that I can use to convert old documentaries from VHS to DVD and even Youtube for classroom use!  I tried this some time ago with the following results.

Generally Speaking,