baseConvert woes

[Ledigimate]

Dear forum

The baseConvert function tells me that the numbers 3614123224 and 7909090520 has the same binary representation! WHY??

Code: Select all

put baseConvert("3614123224", 10, 2) is baseConvert("7909090520", 10, 2) -- yields true

This has been causing me huge frustration. Can someone explain what's going on here?

Regards,

Gerrie

[Ledigimate]

Never mind.

I see the dictionary says baseConvert can only handle numbers between zero and 4,294,967,295 (2^32 - 1).
The number 7909090520 is thus too large for baseConvert to handle. I guess I'll have to write my own function to convert larger numbers!

Gerrie

[bogs]

I thought -hh already did that? Or maybe I'm thinking of someone else... at this stage, it is so hard to tell

There was this multipage thread about large numbers, maybe the answers are in there.

[dunbarx]

Hermann did indeed write a "long" addition, subtraction, multiplication and division gadget several months ago

It's around here somewhere.

Craig

[FourthWorld]

What does the number represent? Is it an actual quantity, or a decimal representation of byte values? If the latter, the binaryEncode and binaryDecode functions may help, since they can operate on a series of values in one pass, with lots of conversion options.

[Ledigimate]

What does the number represent? Is it an actual quantity, or a decimal representation of byte values? If the latter, the binaryEncode and binaryDecode functions may help, since they can operate on a series of values in one pass, with lots of conversion options.

Kind of both. The number is an actual quantity calculated as the sum of four 32-bit integers, and only one of the four integers is the decimal representation of a 4-byte chunk of binary data. I'm trying to write a hashing algorithm.

But not to worry, as I don't actually need to convert the REAL sum of the four integers to its bit-representation. I only need the bit-representation of (theSum bitAnd 4294967295), which leaves a 32-bit integer. So the baseConvert function will work just fine.