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Bash: find out PI

Uncategorized • March 25, 2011 • By Juje007 @ 11:27 pm • • 0 Comments

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A long time ago I wrote a script to find out the numbers behind the number PI but that was written in VBS. And today I wanted to recreate that script but than in Bash. I succeeded completely and here is the code:

#!/bin/bash
x=4;
endNr=$x;
lastUsed="+";
counter=3;
while [[ $counter -lt 1000000 ]];
do
    if [[ $lastUsed == "+" ]];
    then
        newNr=$(echo "scale=30; $x/$counter" | bc);
        endNr=$(echo "scale=30; $endNr-$newNr" | bc);
        lastUsed="-";
    else
        newNr=$(echo "scale=30; $x/$counter" | bc);
        endNr=$(echo "scale=30; $endNr+$newNr" | bc);
        lastUsed="+";
    fi;
    counter=$[$counter+2];
    echo $endNr;
done;

Usage (Linux):

Step 1: Put the code inside a file and save it as a .sh file.
Step 2: In command line give the file a chmod of +x (eg. chmod +x fileName.sh)
Step 3: Than run the file (eg. ./fileName.sh)

And here you go.

Have fun!!