Welcome to M.E. 205: Computers and Programming Countdown to the due date: 05 December 2008 17:00:00

11/18/2008 The Home Stretch!

Here we are 17 days out. Congratulations to those who have finished and good luck to all those still planning to complete ME205 this semester. Be sure to check out the Progress UpDate on the left to see how you compare. To help us out, let me make three important announcements.

Office Hours have been changed and moved. Be sure to check the proctor page for the new times and locations. In short, all office hours now take place in ETC 3.112 to accomodate the larger crowds. Still bring your laptop if you have one since the lab computers may fill up quickly. New hours start Thursday, November 20th!

The answer to the question we have been getting a lot: I am on unit x, can I still pass the course? The answer: theoretically yes. And more importantly. We want you to finish and will do what we can to help out, BUT we cannot play favorites. Consider these numbers.

With 159 students and 17 units/student, the proctors must grade a minimum (assuming everyone passes the first time) of 2703 tests. Since all of you have collectively passed 1311 tests so far in the first 79 days of the semester, the proctors have graded an average of 16.6 tests/day. This means that there are 1392 tests left to grade in 17 days. That is 81.9 Tests/day! Simply put, we can't pull yours out of the queue and grade it early. Not fair, and logistically impossible. We will grade as fast and as fairly as possible. The best thing you can do is be prepared to take the next test as soon as it is available and pass it the first time.

We are still getting some students turning in some tests that clearly have not been run through a compiler. These students have either missed the directions below or are lost and fishing for hints without doing the work. Compile your code or feedback to you will be intentionally sparse so we can focus on students doing the work. If you are lost and have a specific question to ask with difficult code, be sure to include it in your submission.

Good luck, Dr. Pryor

10/21/2008 Review Test Clarification

There are quite a few coming up on their first Review Test so the policies discussed that first day may be a distant memory. If so, scroll down and review the 'First Day' presentation to help you avoid some of the more common mistake we are seeing.

I have also added the following paragraph to the top of the Reveiw Units to remind you of the basics each time a Review test looms. Remember, Review Tests must be taken during office hours. You must start the review test at least an hour and half before the end of office hours. Review tests are open book and you may look at the material in units you are being tested on. Create, compile and test all code before submitting it. Don't forget, the Proctors will want to look at your test with you when you are finished and ask a few questions.

Also for those of you curious where you are relative to the rest of the class, be sure to check out the Progress Update on the left menu. Be sure to click on the 'Compare Your Performance' link at the top of the Progress Update page. Congrats (almost) to me205-084!

Good Luck, Dr. Pryor

10/15/2008 Looming Incentive Date.

It looks like about 25 people are in a position to benefit (or already have benefited) from the October 17th incentive date. Its a great time saver so be sure to put R3 November 7th incentive date on your calendar and make a plan for getting to R3 by then.

Good luck, Dr. Pryor

10/14/2008 Back to basics.

Congratulations to that one student who has pulled ahead (check the Progress Update) of the pack and is likely to finish as soon as next week. You should thank him or her as as well since it is one less person who will need help in the closing weeks of ME205. Today I proctored a total of 7 students during office hours (and 2 of those were ME218 students taking advantage of my light load!)

Let me take a moment and put two bits of advice back at the top of the pile.

• Compile Every Time! We still get students who think that they can write code directly into Word and submit it. Wrong. The Proctors will compile it, and if it doesn't work, you've got to take another test to pass the unit. Build and test your programs in .NET and then C&P your finished programs into a .txt file or .doc file for grading.
• Send all queries to BOTH me and the proctors (me205@mail.utexas.edu). You have a much better chance of a quick reply with 5 people checking their email rather than just me.

Good luck, Dr. Pryor

10/13/2008 Talking shop....

Those of you industrious enough to attack a unit on Texas/OU weekend may have had some problems, and since you are budding programmers, let's talk a little shop.

What happened? Apparently a Firefox extension working on the computer of a student (nothing malicious apparently) managed to download a 320 Gigabyte file and tried to store it on their share in the AUSTIN domain (which is essentially nothing more than some large hard drives that UT is kind enough back up for us so we don't have to). Of course this not only exceeded the student's quota, but also triggered a quota limit for the ENTIRE subset of mechanical engineering students. The system automatically decided that no one should write anything else until this was fixed. Of course, the whole thing took place around 5pm on the Friday before Texas/OU weekend.

What happened next? This behavior is of course a bug that needed to be fixed, at the AUSTIN domain level - beyond use mere me205ers and even the Department. By Sunday, the problem was fixed and a correct enforcement policy was implemented. Now it was only a matter getting the new policy in place for every student. By the end of today, everything should be back to normal, and students who did not use the share this weekend don't even know it happened.

So what does this mean for me205? Nothing really. Servers occasionally go down, printers break, hard drives crash and batteries die. One big reason NOT procrastinate in ME205 (and on any assignment in general) is to ensure that these events beyond our control do not negatively impact our grade. Based on this, I have two suggestions. 1) The obvious one: finish early, and 2) Put as much of the process under your direct control as possible. If you haven't yet, purchase .NET at the Campus Computer Store or get your free copy using Windows Live. You can still back your files up to your share (or even use the application server when it is available, but now you have flexibility and redundancy when it comes to finishing your assignments.

Hook'em, Dr. Pryor

10/6/2008 Just 2 Months Left! (But do the math)

60 Days is a lot of time, but remember this includes the possible 48 hours for each test to be graded, the days you study for other tests, OU/Texas weekend, Thanksgiving, and other events where you don't want to be sitting in front of a computer. If you haven't started yet, look at your calendar and tell me how many days do you personally still have to work on units for ME205?

Good luck, Dr. Pryor

10/2/2008 Compiling every time.

By today over 100 of you can easily tell me what the following code will print to the screen. Congratulations!

	int a = 3;
	int b = 5;
	int c = 7;

	printf("%d %d %d\n", a, b, c);

But what about this code?

	int a = 3;
	int b = 5;
	int c = 7;

	printf("%d %d %d\n", a+b, b++, c-b);

When I run this code, I get "9 5 1". What did you think you would get? Using the code below, I get "9 6 1"

	int a = 3;
	int b = 5;
	int c = 7;

	printf("%d %d %d\n", a+b, ++b, c-b);

Huh? There are two lessons here. The first is the most important and broad. Compile Everytime! Every program you create, you should compile and test. Every bit of code that we ask you about (like the ones above) should be compiled. The second lesson is that C can do strange but, in the end, logical things. Above, the statement b++ is short for the statement b=b+1, which is a assignment command right? Most compilers (but not all) will perform embedded commands first.

Now, what is the difference between b++ and ++b? Both are short hand for the command b=b+1, but there is an important difference. ++b changes the value of b immediately. b++ changes the value for the next statement. In other words if b is 5, it remains 5 in this statement (which above was just the embedded statement). This difference is reflected in the difference between the two outputs. Clear as mud right? The important thing to do is test and compile, test and compile, etc. until you are comfortable that you understand the behaivor of the compiler.

"Wait a minute!" you understandably demand. "What does any of this have to do with my being a mechanical engineer?" My response: Hopefully as little as possible, but designs will be simulated, and motors need controllers, etc. Personally, I try keep my code as simple as possible and leave these tricks to the CS guys, but it is important to know they are out there.

Good luck, Dr. Pryor

9/25/2008 Most common questions answered (and how to ask them)

First, the second part: How to ask a question? Of course, there is chat and office hours, but we are also getting a lot of questions via email, which is fine. My suggestion is to ALWAYS email both me AND the proctors. That way, you are waiting for any one of 5 people to check their email instead of just one. When we answer, we will hit reply-all, so we all know you have gotten the information you need.

So here are discussions on the most common questions

1. Integer vs. Floating Point Math: If you take two ints (declared variables or numbers) and divide one by the other, the computer will give you an integer in return. For example, 1/4=0. Since 0 is the closest integer. In fact, most computers will always round down. So if you are working with floats, but don't want to make a variable to store the float, how do you let the computer know it is a float? Simple, try 1.0/4.0 which will give a float for an answer or 0.25.
2. Getting Started....: Almost every other question I am getting is from students just starting Unit 01 and something from the Firstday.pdf has slipped their mind. For example, using me205-xxx to access the Test Submission System, but me205 is the username for all the units. If you are just getting started, you might want to review it.
3. Word 2007, Mac, etc.....On the one hand, I am really excited about all the different sofware and hardware students are using these days. We got .NET 2003, 2005, 2008, Citrix, XP, Vista, MAC, Linux, Office, Office2007, OpenOffice. Choice is great. But we don't have the resources to test every unit and test on every OS, Hardware, SFW combination, so if you see something weird, let us know. I do know that on a PC with Citrix on IE or FF using XP and Word 2003, (phew!) everything should work great, and we will keep fixing things for other platforms as we find them.

Good luck, Dr. Pryor

9/16/2008 Unit1-a-thon?

If you look at the progress update, we still have 117 students sitting on units 00 or 01, so Unit1-a-thon is off to a, er, slow start. At the same time, I proctored three R1 Review Tests Today! These three plus the other three students here are getting questions answered quickly....But that still left me with some time so here are a couple fun items I found to share....

Some of you may have noticed that I use "stdio.h" in the Hello World example, but unit 01 uses <stdio.h>. The more proper form to use is <stdio.h>, but both work just fine. What is the difference? Using quotes or brackets simply tells the compiler where to look first for the file. If you use quotes, the compiler first looks in your local directory, and THEN looks in the system directories. If you use brackets, the compiler FIRST looks in the system directory and THEN in your local directory. So if there is only one stdio.h file, then there is no problem. If there is an stdio.h file in BOTH directories (say you are so cool, you write your own), you can use quotes to ensure the compiler uses your file instead of the system's file.

I found a great web site call ProjectEuler.net. The idea is to learn a new programming language by solving incrementally harder math problems. You can check out the problems here. As you work through the first few units, you will see the difficulty is about the same for the first few challenges in Project Euler.

Happy Coding!

9/10/2008 Unit1-a-thon!

Well all the ME205 orientations are complete and all of you are out of the gate running....or walking.....or standing on your way to a hopefully happy conclusion for ME205.

Here are a couple hints, ideas, and policy announcements:

• All the Citrix documentation has been updated and tested by students, proctors and the IT department. If you still having any problems, definitely come by office hours.
• If you have any email questions, always send them to both me AND the proctors (me205@me.utexas.edu). This increases your chances of getting a prompt response.
• As the title says, let's make a concerted push to get everyone through unit 1 this week. This way, WE know you know how to use the tools you need, and YOU know better what it will take time-wise to complete the course. Unit1-a-thon!
• Even better! We have created Review Test incentive dates. If you complete the Review Test by the date given below, you can answer any one question on that Review Test with an X for full credit, saving you even more time in the long run! The dates are below

9/2/2008 Welcome!

You have reached the home page of ME 205. This course is a basic introduction to the C, Matlab and Java programming languages. It is taught by Dr. Mitch Pryor at The University of Texas at Austin. If you are visiting this page for the first time, the links below will lead you to all the information you need to get started.

• Syllabus- The official syllabus for ME205
• Orientation Presentation - A copy of the presention from the orientation day. (.pdf file)
• Test Submission Page.The web interface used to take and submit tests.
• Office Hours - A list of the Office Hours for the TA and Instructor.
• Application Server - Links to the login page for the Citrix Application Server.

Good luck! Don't hesitate to contact us via chat, email (the instructor or the proctor), or find us the old fashion way: in person during office hours!