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Simple As Pi!

Pi (not pie) is the name of a mathematical constant that represents the ratio of a circle's diameter to its circumference. Pi is an irrational number that cannot be represented exactly as a fraction.

With the super-computing power available as of 2015, Pi has been calculated to 13 trillion digits. But for most purposes, using an approximation of 3.14 or 3.1416 is sufficient. My junior high math teacher required us to use 3.1416.

So . . . pi.gnance is an approximation of Raspberry Pi!

March 14 is Pi Day!

Each year features Pi Day on March 14, or 3/14. During 2016 a special Pi day with two additional digits of precision occurred on 3/14/16. And during 1593, the Pi Day to end all Pi Days featured a total of 7 digits of precision, 3/14/1593. It will be almost 14,000 years on 3/14/15927 before a date with 8 digits of pi will roll around (assuming of course that humanity survives the Y10K bug)!

Cook Your Own Pi

Want to use your Raspberry Pi to approximate the value of pi? Here is a short recipe written in C by Dik Winter that will calculate pi to 800 digits! (Note that 10 decimal digits for Pi, 3.1415926536 is sufficient to calculate the diameter of the earth with a margin of error of less than one foot.) To use this program:

  • Save the following three lines of C code to a file named calcpi.c on your Raspberry Pi
    int a=10000,b,c=2800,d,e,f[2801],g;main(){for(;b-c;)f[b++]=a/5;
  • Open a terminal session, and from the directory where calcpi.c exists run the following command to generate an executable program called calcpi
    gcc calcpi.c -o calcpi
  • From the same directory, run this command:

Your Raspberry Pi 3 will execute the program in a fraction of a second and display the following output:

Pi> ./calcpi

Most of you have probably already noticed that the number 42 (the widely accepted answer to life, the universe, and everything) appears 4 times in the first 800 digits of pi. It has long been suspected that the actual question to go with the answer 42 is encoded somewhere in the first 3 trillion digits of Pi, but as of yet nobody has been able to decode it.

Raspberry Pi Wallpaper - Don't Panic

The Raspberry Pi Foundataion has a really cool logo. It's very simple and very recognizable, and it's also very proprietary. Their logo appears on the desktop of the Raspbian distribution, but their usage policy makes it clear that it won't be appearing on pi.gnance.com.

For a little variety, you might want to consider a desktop wallpaper from pi.gnance.com. Our wallpapers not only feature the time-tested pi symbol, they also include the words DON'T PANIC in large friendly raspberry-red letters.