## #math - Wed 28 Mar 2007 between 00:12 and 00:29

### NY Lost Funds

 john_sheu I went off and tried to do some crap with exp^ix |Anubis __snake: what is the small e symbol ? TRWBW john_sheu: that works too john_sheu well, in my case, evidently it didn't :-P xor The number represented by each sequence is \sum^n_{i=0}{f_i*b^i}with each f_i < b __snake anubis: greek letter called epsilon TRWBW xor: well you can, you just have to be very careful __snake anubis: use any favorite letter instead of it if you don't like it xor TRWBW: I already knew that you can TRWBW xor: if it's a computer problem, and you only have native 32 bit numbers, you can work in base 32, you just need to sometimes represent a number as a pair of numbers for example xor ok, and... TRWBW xor: not sure what you are asking. the simple description of a base b algorithm for division or addition or multiplication or such sometimes deals with numbers bigger than bxor: you deal with it by sometimes using 2 numbers, for example in addition, an extra "carry number"xor: that is 2 numbers to represent 1 number xor okLong divisionBut I still don't know how to divide the 2 digit numbers TRWBW xor: all i'm saying is that working in numbers larger than b isn't an issue, because you can represent them using two numbers, which gives you numbers up to b^2-1, or more if you need too. in general that should be enough, just two digits for intermediate values xor I can represent numbers up to any size, using sequences of digitsbut that doesn't help me divide TRWBW xor: if your problem is not knowing how to divide, look up "long division" on the web xor I know the long division algorithm TRWBW xor: i'm sure any of those will be a more detailed explaination than i would care to type inxor: clearly not, if you can't do it xor But I don't know how to divide the 2 digit remainder numbers TRWBW xor: either you have found a flaw in the long division algorithm, which would be pretty big news, or the long division works, and your inability to do it means you don't understand it. i don't see any possibly middle ground. xor For example, 4 into 15 (base 10) TRWBW 4*3=12, 15-12=3, 15=4*3+3 xor Clearly.But how did you come up with those numbers? TRWBW the largest digit 1..9 that times 4 is less than 15 is 3 xor hardly efficient TRWBW xor: didn't say it was, but after you have that, everything else is just effeciency improvements xor There has to be a better way than brute forcewell, doesn't have to be, but it feels there should be TRWBW xor: try a lookup table xor The bases we are working with are 2^32 or 2^64A lookup table wouldn't even fit in memory TRWBW xor: then if it's on a computer, use the builtin division for 2^w your word size