Name: [116] Erik Thompson
Member: 108 months
Authored: 44 videos
Description: Hi! I am currently a full time student at California State University Long Beach. I recently began to do research in molecular dynamics. I have interests in Python programming, physics, chemistry, and 3D simulation. Also I like bird watching! Here are some of photos I've taken: http://ww ...

VPython: Projectile Motion 2 [ID:080] (2/9)

in series: VPython - Physics and 3D in Python

video tutorial by Erik Thompson, added 03/07

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This episode continues from the last episode in which a ball was dropped to the earth. We modify that 3D program so the ball is thrown horizontally from the top of a building.

Full source-code is in the wiki.

Uploaded on 18th November 2006, running time 12 minutes.

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Video statistics:

  • Video's rank shown in the most popular listing
  • Video plays: 54 (since July 30th)
  • Plays in last week: 3
  • Published: Sometime before 1st March 2007 (in other words - we don't remember!)

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25. Anonymous Thu, 02 Sep 2010 21:39

Good job.

24. gordie howe jersey Wed, 04 Aug 2010 21:16

it is good

23. 最安値に挑戦中 3日間限定 Thu, 10 Jun 2010 10:07

Great video. It illustrate very well the fundamentals of vpython.

22. Bogner Zipper mit Kapuze Umweltfreundlich Innenfutter aus 100% Polyester Sun, 06 Jun 2010 02:23

Awesome series. Although, I would appreciate a slight increase in the speed of the videos, its quite slow right now, which might be easier to understand for some, but I think the average Vpython newbie might be quicker than you give them credit for.

21. jasa SEO, Backlink, Blogwalking murah Sun, 21 Mar 2010 10:02

Thank you for the help!

20. anonymous Fri, 13 Nov 2009 20:38

I like the fact that the vodcasts show mistakes ... I think that students can learn something from the troubleshooting process.

19. anonymous Thu, 05 Nov 2009 09:06


I am phd studant of physics at universidade federal de santa catarina /Brazil

and i like very much of programming languages. Now, i am looking a bit about python. Very cool yours videos.


18. anonymous Sun, 25 Oct 2009 12:25

c'est superbe ! bonne courage , merci d'avoir sacrifié un peu de temps pour les autres êtres humains



17. anonymous Sun, 11 Oct 2009 11:03

Hi, good job on the Python tutorials, I'm currently on video number 2 and is enjoying it. The picture is clear, good sound, well explained, fun topic, keep up the good work.

Regards Christian from Norway.

16. anonymous Sun, 02 Aug 2009 07:28

nice video keep it up

15. anonymous Sat, 01 Aug 2009 10:01


14. anonymous Mon, 06 Jul 2009 15:54

its good to have this kind of webpages to lear easy (:

13. anonymous Fri, 29 May 2009 16:58

Nice tutorial!! Excellent job!!

12. anonymous Wed, 20 May 2009 14:26

Hello, Erik.

I really like your tutorials i only did the first 2 so far, but allredy learned alot, after i didn't suceed in C++, i found python, and i really wan't to make my own 3D rpg. I hope you will make some tutorials on how to use blender with python to make characters and animations or something(If you haven't allredy).

I'll keep following your tutorials. Cheers and i hope for even more.

11. anonymous Sun, 22 Mar 2009 14:55

cool video for getting a quich intro into 3D modelling using vpython.

thank you for your great job.

10. anonymous Fri, 09 Jan 2009 13:46

I think Vpython is a great idea to teacher/learn physics.

But is possible change the parameters or initial conditions without open the source file and edit it?

Is possible a dynamical interaction using controls to change the initial conditions: velogicty, positions etc ?

9. anonymous Fri, 14 Nov 2008 07:10

I am referring some students at the high school level, who I mentor, to these videos as a way to get them started with VPython. Your pace and style is not threatening for them and is an awesome resource! Thanks for doing these! Are Bruce Sherwood and Ruth Chabay aware of your efforts?

Thanks for pointing out the bug and suggesting the use of an additional variable. It certainly would have made sense for this example.

7. anonymous Tue, 20 May 2008 15:15

Hmm, I think it is better to define variables for start height and stuff.

Because now you updated the start position to 102 in one place, but still have 100 in the actual ballY equation. That happens when you use integer constants everywhere.

6. anonymous Thu, 14 Feb 2008 14:08

Another interesting tut would be using the physics package embedded in the Blender 3d environment. This package is completely accessible from the python environment inside of Blender 3d.

5. anonymous Wed, 19 Sep 2007 12:41

I'm impressed! I want to see more of these awesome kinds of your tutorials!!!

4. anonymous Thu, 06 Sep 2007 22:28

you are awesome. Learned a lot. Thanks.

Yeah these tutorials are really nice. I made 3 additional walls in the scene from the first tutorial just because the instructions were clear.

Keeping the error and debug process in future projects will really show a nice aspect of the development process since half the time you are trying to decipher error messages or trouble shoot anyway. Good job. Keep it up.


Thanks for your comments. I was too lazy to go back and make edits. I figure it's good to see that programming is half about making and finding bugs anyway =). In the later videos I did write the code ahead of time in an effort to waste less time but they still wound up being a half hour so I'm not sure how successful those were but they were fun to write.

For the Linux videos on the first few episodes I used software called xvidcap (or it might have been gvidcap, i forget, they are part of the same package I believe):

That program sometimes works well and is pretty easy to use, but sometimes it drops frames like crazy. I think it is dependent somehow on your hardware and drivers but I became frustrated and switched to using Windows and software called CamStudio which works well:

ShowMeDo also has a page about screencasting on their wiki:

Good luck! Feel free to share anything you create here at ShowMeDo if you are so inclined. =).

Mr. Thompson!

Very Good Tutorial!!!

I liked the fact that you did not delete your spelling errors.

Your structured step by step approach combined with your use to the Vpython window to check your progress, demonstrates a excellent use to these tools.

I am learning Python and VPython for use in my classroom. Please tell share with me the software tools you used to create the tutorial.

I'm a high school math teacher.

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At Showmedo we believe the community can play a vital role here and also say thanks for the tools and software that make our lives easier. If you have a piece of software you love or a programming langugage you are enthusiastic about, why not make a screencast showing others how to use it? All the stuff you wish you'd been told, the tips, tricks, insights that would have saved you time and frustration.

Screencasting is easier than you think, and we're happy to help you. You can emailus for advice or just use some of the how-to screencasts on the site. This screencasting learning-pathis a good place to start.

Kudos and Thanks for Erik

By the Same Author



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