Animation video of rgl in action

Duncan Murdoch just posted a youtube video presenting an animation clip of a 3d rgl object.

Duncan even went further and wrote an explanation on how he made the video:

here are the steps I used:
1.  Design a shape to be displayed, and then play with the animation functions to make it change over time.  Use play3d to do it live in R, movie3d to write the individual frames of the movie to .png files.
2.  Use the ffmpeg package (not an R package, a separate project at http://ffmpeg.org) to convert the .png files to an .mp4 file.  The individual frames totalled about 1 GB; the compressed movie is about 45 MB.
3.  Upload to Youtube.  I’m not a musician, so I had to use one of their licensed background tracks, I couldn’t write my own.  I spent a lot of time picking one and then adjusting the timing of the video to compensate.  Each render/upload cycle at full resolution took about an hour and a half.  It’s a lot faster to render in a smaller window with fewer frames per second, but it’s still tedious.   It’s easier to synchronize if you actually have a copy of the music locally, but Youtube doesn’t let you download their music.  So the timing isn’t perfect, but it’s good enough for me!

Wonderful work Duncan, thanks for sharing!

Announcing R-bloggers.com: a new R news site (for bloggers by bloggers)

I already wrote about R-bloggers on the R mailing list, so it only seems fitting to write about it more here. I will explain what R-bloggers is and then move to explain what I hope it will accomplish.

R-Bloggers.com is a central hub of content collected from bloggers who write about R (in English) and if you are an R blogger you can join it by filling in this form.

I built the site with the aspiration to  help R bloggers and users to connect and follow the “R blogosphere”. When I am writing these words, R-bloggers already has 17 blogs in it, and I hope for many (many) more.

How does R-Bloggers operate? This site aggregates feeds (only with permission!) from participating R blogs. The beginnings of each participating blog’s posts will automatically be displayed on the main page with links to the original posts; inside every post there is a link to the original blog and links to other related articles. While all participating blogs have links in the “Contributors” section of our sidebar

What does R-Bloggers offer it’s visitors?

  • Discover (for all): Find new R blogs you didn’t know about. And Search in them for content you want.
  • Follow (for people who don’t use RSS): Enter your e-mail and subscribe to receive a daily digest with teasers of new posts from participating blogs. You will more easily get a sense of hot topics in the R blogosphere.
  • Connect (for facebook users): Click on “Fan this site” to become a “fan” of R Bloggers. You can then “friend” other people and share thoughts on our wall. Or just by leaving comments on the blog.
  • Participate (for bloggers): Add your R blog to get increased visibility (for readers and search engines) with permanent links on our Contributors sidebar. Your blog will also gain visibility via our e-mail digest and through your presence on the main page with posts.

Who started R-Bloggers (and way)? R Bloggers was started by Tal Galili (well, me).  After searching for numerous R blogs I decided that there must be more R blogs our there then he knows about, and maybe the best way for finding them is to make them find him.

After writing about it in the R mailing list, I got some good feedbacks but also questions about why use only R blogs and not all the R feeds that exist. Who is the website actually for (when there are services like Google reader for us to read our feeds with), and what am I hoping it will do. So here is what I answered:

For me there are two audiences:
One is that of the web 2.0 power users. That is, people who know what RSS is and use it, maybe evern write their own blogs. These people have only one problem (as I see it) that R-bloggers tries to solve, and that is to know who else lives in their ecosystem. Who else they should follow.
For that, google reader recommendation system is great, but not enough. A much better system is if there was a one place where all R bloggers would go, write down their website, and all of us would know they exist. That is what R-bloggers offers for the power users. I think this is also why over 20 of them subscribed to the site RSS feed.
BTW, The origin of this idea came to me when I was trying to find all the dance bloggers for my wife (who is a dance researcher and blogger herself). After a while we started http://www.dancebloggers.com/ while knowing of only 10 bloggers. They list now has over 80 bloggers, most of which we would have not known about without this hub.
The same thing I am trying to do for the R community, that is way I hope more R bloggers would write about the service – so their network of readers which includes other R bloggers would add themselves and we will all know about them.
If that was my only purpose, a simple directory would have been enough. But I also have a second one and that is to help the second audience.

The second audience I am thinking of are people of our community who are not so much early adopters (and actually quite late adapters) of the new facilities that the new web (a.k.a: web 2.0) provides.
To them the all RSS thing is too much to look at, and they are used to e-mails. And because of that they are (until now) disconected from many of the R bloggers out there, simply because it is in-efficient for them to go through all these blogs each day (or even week). So for them, to see all the content in one place (and even get an e-mail about it) would be (I hope) a service. I believe that’s why 5 of them (so far) has subscribed via e-mail.
I also hope teachers will direct their students to this as a resource for getting a sense of what people who are using R are doing.
Another thing that hints me about the R community is seeing how the “facebook fan box” is still empty. Which tells me that (sadly) very few R users are actively using facebook as a means for connecting with the outer networks of people out there.

All I wrote also explains why R-bloggers will only take feeds of bloggers and only (as much as can be said) their posts that are centered around R (hence the website name :) ).
It both follows what Gabor talked about – having a site who’s content is only about R. But also what I wish, which is to have “content” in the sense of articles to read (mostly). And not so much things like news feeds of wikipedia or new packages published.

I hope this post will both notify people about this new resource, encourage more R bloggers to join, and will help for future people to better understand what this R-Bloggers thing is all about :-)

A web application for R’s ggplot2

One of the exciting new frontiers for R programming is of creating website interfaces to R code. At the forefront of this domain is a young and (very) bright man called Jeroen Ooms, whom I had the pleasure of meeting at useR 2009 (press the link to see his presentation).

Today Jeroen announced a new version (0.11) of his web interface to ggplot2. See it here:
http://www.yeroon.net/ggplot2/

As Jeroen wrote:

New features include 1D geom’s (histogram, density, freqpoly), syntax mode (by clicking the tiny arrow at the bottom), and some additional facet options. And some minor improvements and fixes, most notably for Internet Explorer.
The data upload has not been improved yet, I am working on that. For now, it supports .csv, .sav (spss), and tab delimited data. Please make sure your filename has the appropriate extension and every column has a header in your data. If you export a dataframe from R, use:
write.csv(mydf, ”mydf.csv” , row.names=F). If you upload an spss
datafile, none of this should be a concern.
Supported browsers are IE6-8, FF, Safari, and Chrome, but a recent browser is highly recommended. As always, feedback is more than welcome.

Here is a little demo video that shows how to use the new features:

The datafile from the demo is available at http://www.yeroon.net/ggplot2/myMovies.csv.

I wish the best to Jeroen, and hope to see many more such uses in the future.