To celebrate 3.14 for 2009, I made the attached worksheet with an interactive Pi Chart (also a pie chart) to plot the relative frequency of the digits of pi in various bases.  Enjoy.

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The guts of the worksheet is the following:

basesymbols := Array(0..35, ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"]):

n := 200; # number of digits
k := 10; # base 
N := ceil(log[10](k)*n)+1;

approxPi := round(evalf[N+1]((Pi-3)*10^(N))):

PiList := map(x->basesymbols[x],convert(approxPi, base, k)): 

PiString := cat(op(map(convert, PiList[1..n], string))):

T := [StringTools:-CharacterFrequencies(PiString)]:

Statistics:-PieChart(T, color=blue..magenta);

The Maplesoft office is currently in the process of being burried in snow and many of us are getting ready to head off for the holidays.  Before leaving, I wanted to share this great animated GIF created using 3d plots.  It was sent to me by Bruce Char at Drexel University. The greeting and the Maple script to generate it are after the break.

In my previous post, I was parsing data out of HTML tables so that I could glean some trivia from it.  My true goal was to compile data out of dozens of such tables and so I needed a way to do the whole process in Maple.   So, now, here is how I used Sockets and StringTools to automate the whole process.

Recently there was some discussion in the Maplesoft office about unisex baby names (that is, names that nearly as likely to belong to males as females). Whenever discussing names, I usually head to the US Social Security Administration's wonderful baby names site. They have data on the top 1000 male and female names for children born in the US each year for more than the last century (that includes about 80% of names). They slice the data a little by US state, and popular names for twins and such, but they do not include data on unisex names. So, I applied Maple to the task.

Recently, I was reading about random.org again.  It is an online random number generating service that uses atmospheric noise gathered from radios tuned between stations as a source of randomness.  It has been running more or less continuously for about ten years.   On their analysis page there is a nice pair of bitmaps (scroll down past the Dilbert comic) that contrast their random bits with those from one version of the PHP rand() function. Basically this demonstrates how easy it is to create a pseudo-random number generator that is periodic with too small of a period.

I decided to take a look at Maple's random number generator in comparison.