Online and Free Calculators and CASs

I made a couple of minor edits to my Wiki page about online basic calculators, scientific calculators, graphing calculators, CAS systems, and plotting utilities today.

It still blows me away how much is available online and how good the quality is. Yacas (yet another CAS) has a tab called My Yacas that provides quick access to the list of commands and to the actual CAS engine - no download required.

Now, if only math students had the kind of access to computers and the internet that would allow them to use these tools routinely in school.

Update: Don't miss the link above to the actual page listing online calculators, CASs, graphing utilities etc.

Mathematic Notation

I ran across a post today on the SquareCircleZ blog, lamenting the effect of some of the poor choices of notation that we use in Mathematics.

It reminded me of the trouble that I have been having saying that cosine is x/r and then making r=1 to get a unit circle. Now x=cosine and we graph the values as y = cos x (what is x!!!).

One of the commenters makes an interesting suggestion about the use of brackets. If we adopted this idea, we could see the difference between 5(x) and f(x).

1. David Speyer said,

   June 17, 2007 at 12:08 pm

   By the way, this is Mathematica’s notation. “()” indicates order of operations, “[]” indicates application of functions, “{}” indicates an ordered pair or a list. So

   ParametricPlot[{Sin[t], 2*(Cos[t]+1)}]

   would plot an ellipse whose x-coordinate is Sin[t] and whose y-coordinate is 2*(Cos[t]+1). (Also, “[[]]” indexes into a vector or array, but pedagogically we want to discourage students from thinking of an array and a function as different objects.)

   I find that I have very little trouble making these distinctions, even when I’ve been away from the software for several months, so I think it would be easy for experienced mathematicians to switch to the new notation.

Cubicle Freakout

I was enjoying Michelle Malay Carter's blog this morning. She has a link to the Wii Remote SmartBoard Video, suggesting it makes the Wii a business expense! She also has a nice collection of funny YouTube videos and a link to a Flash game, quite unlike the CLIPs ones, called Cubicle Freakout.

Incidently, PhD graduate student Johnny Lee's Wii Project page lists some other neat things to do with the Wii Remote. They might even make a cool Science Fair Engineering project.

Here is an example of one of the YouTube videos she features:

Underestimating Children?

The New York Times reports the following conversation between a child and a contender for the U.S. presidency:

“Who is your favorite author?” Aleya Deatsch, 7, of West Des Moines asked Mr. Huckabee in one of those posing-like-a-shopping-mall-Santa moments.

Mr. Huckabee paused, then said his favorite author was Dr. Seuss.

In an interview afterward with the news media, Aleya said she was somewhat surprised. She thought the candidate would be reading at a higher level.

“My favorite author is C. S. Lewis,” she said.

Sometimes truth is funnier than comedy.

See Knowledge being created and negotiated in real time

Tim Hawes' recent blog post references a site where you can watch anonymous Wikipedia edits being made. Read the FAQ to see the various databases and APIs that are being used to create it.

Man fired for posting a Dilbert Cartoon

I think that I may need more than one blog so that these posts aren't so unrelated to one another. But I got a kick out of this posting to the Dilbert Blog.

Disclaimer: No one I have ever worked with or for in any way resembles a drunken lemur.

Comparison of E-Learning Screen Capture Tools

I have been involved with a group looking at the pros and cons of using Techsmith's Camtasia, Adobe Captivate and Adobe Presenter. A wiki with some youtube videos and a preliminary comparison chart is available for editing.