Read Me

Collatz Tool README
@License GPL v2.1
@author Matthias Werner <wmatthias at users.sourceforge.net>
@date 17. 05. 2011
=============================================================

WHATS THIS:
Collatz Tool is a little console based program to generate collatz numbers. 
The basic collatz rule is
           
x_(n+1) =  { x_n/2, if x_n is even,
             factor*x_n+1, if x_n is odd. }

where factor is 3, but you can change the factor by the option -f.
You control the program by parameters on console as follows:

OPTIONS:
  -f factor             - collatz factor (3)
  -s startnumber        - number where to start (23)
  -m maxloops           - maximum of loops (10000)
  -o output             - output file for data ("output.csv")
                          (either Standard or Alternative Format)
  -n                    - no output, only test for termination (faster)
  -t numbers            - tests algorithm with iteration on startnumber
  -a                    - alternative output
  -h                    - this help text

If no options are given, it will create standard output of collatz numbers to "output.csv". 

HOW TO START:
WINDOWS XP:
To get this thing started press WindowsKey+R or go to startmenu and "Run...". 
Enter "cmd" into that little input window and now you get a black screen aka console ...

WINDOWS 7:
Go to Startmenu and type "cmd" right into this search field and "Enter" it. 
If you need admin rights, you will have to press "Ctrl+Shift+Enter" to start 
the console with admin rights ...


... navigate to the folder, e.g. "C:\Collatz" with the "cd" command:
"cd C:\Collatz". If you want to work on a different drive, then you will have to 
switch first by typing:
"D:"
and then navigate as explained above.

Now you have access to collatz.exe. Use parameters to control the output.
Example, with startnumber=7, factor=7, maxloops=1000, output=myoutput.csv

collatz.exe -s 7 -f 7 -m 1000 -o "myoutput.csv"
...


LINUX:
Download the source from:

https://sourceforge.net/projects/collatztool

and use the makefile Makefile.Linux to compile.



USED SOURCE LIBRARIES:
bigInt from sourceforge
http://sourceforge.net/projects/cpp-bigint/  
This Library provides arbitrary precision integers.
  
LICENSE:
GPL v2


For analysis you can use matlab, R, gnuplot or whatever you like. 
Just import as csv file and take care of skipping the first line which is 
just a comment and use ";" as separator.
Be careful with importing too large numbers into other programs because most of them are not able to read these correctly.


So have a lot of fun!
wmatthias

Article (german)
http://11235813tdd.blogspot.com/2011/04/collatz-folge-mit-big-integers.html

Images visualizing collatz numbers
https://picasaweb.google.com/102560696045384678534/CollatzProblemBilder