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Talk:Bitwise operations: Difference between revisions
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→assumption of how integers are stored: comments about fairness & symbolism -- ~~~~
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:: Since the task is BITwise operations, then yes, the assumption ia that the binary representation for integers is meaningful. In fact, the binary representation of a value of 75 in REXX (language) is '011011100110101'b or '3735'x (in hex) [on an ASCII machine]. One can do bitwise operations on that, but it would be more or less meaningless. Note that this is regardless of how a MACHINE stores (some) numbers, twos complement binary or whatnot. The task is to see how a LANGUAGE does bitwise, not the machine that it's running on. So it really does depending on how the numbers are stored. Even though my computer is a "32-bit" machine, the limitation of the REXX language's repesentation is not 2^31 or 2^32 (-1), but a limitation that (most) people relate to: "1" followed by so many zeroes; or mathematically: 10^p where p has to be AT LEAST 999,999,999 --- which is significantly larger than any binary number can be stored, and for the most uses, enough for most needs --- but then there are those Mersenne prime people who will be pushing even that limit ... It should also be noted that the REXX language stores numbers in this manner no matter what the underlying hardware supports (or doesn't support). In fact, REXX does arithmetic much in the same manner that humans do (say, in the way one muliplies 11.2 and -17.9 on paper), and as a consequence, there's no rounding in handling decimal fractions. But that's another matter that COBOL enthusiasts (and PL/I) would love (think PICtures). I didn't mean to delve into how arithmetic is performed. -- [[User:Gerard Schildberger|Gerard Schildberger]] 18:33, 23 March 2012 (UTC)
::: I do not think it's fair to say that '011011100110101'b represents the integer 75. It represents a the character sequence '7','5'. If indirect symbolism were legit here, we'd have huge problems, because anything can represent anything if you allow enough indirection stages. --[[User:Rdm|Rdm]] 18:45, 23 March 2012 (UTC)
:::: It's not about fairness. It IS the way the REXX language represents (stores) integers (and every kind/type of number). Now you get it. 75 is stored as the character sequence '75' !! There is no indirect symbolism here, that's just the way the REXX language stores EVERYTHING. No binary integers, no binary floating point numbers, no boolean switches/flags/bits, ... just characters. There is no indirection stages. Just the storing of characters. If you think that's indirect symbolism, then, yes, that's what I've been saying (above), bitwise operations on integers that are stored as characters doesn't make that much sense. But the REXX language does allow it --- but most uses of bitwise operations (on integers) aren't usually performed for arithmetic reasons as such). -- [[User:Gerard Schildberger|Gerard Schildberger]] 19:11, 23 March 2012 (UTC)
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