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1. Re: doing math on arbitrarly large numbers
JoachimSauer Feb 10, 2007 7:55 PM (in response to 3004)That depends on how the arbitrarly large numbers are represented in that bytearrays of yours, we'd need more information to help here.
Usually you use the existing BigInteger and/or BigDecimal classes for that kind of stuff. 
2. Re: doing math on arbitrarly large numbers
796254 Feb 10, 2007 7:59 PM (in response to 3004)Hello,
You mean Achilles heel? Apparently spelling isn't a strong suit, either.
I'm making an app which requires doing math on some
arbitrary large numbers. Since math is usually my
achilles heal, I have no idea how to do this.
Specifically, i have a byte[] number and I'm trying
Who told you that a byte array would be a good way to go?
to implement these two functions:
Ever thought about starting with arithmetic and working your way up?
What happened to abstraction? Shouldn't you create a class that hides the fact that you're using a byte array or something else?
byte[] root(byte[] number,int radix)
Newton Raphson iteration is a good place to start for roots:
http://mathworld.wolfram.com/search/
byte[] pow(byte[] base,int power)
If it's really an integer power, just loop "power" times and multiply the number by itself each time. Not too difficult.
% 
3. Re: doing math on arbitrarly large numbers
800308 Feb 10, 2007 8:04 PM (in response to 3004)alphabet,
for chrisake google it... there are open source "libraries" in java to perform both these functions. it shouldn't take you more than 10 minutes to find both of them.
why does everyone want to reinvent the square wheel all the time? sheesh!
keith.