Arithmetic in Computer Hardware

Re:Arithmetic in Computer Hardware by adgjlsfhk1 on Friday November 17, 2023 @01:19AM (#38300196)

imo the best way to explain 2s compliment is via a diversion through 2-adic numbers. that also lets you explain the really fun trick where you can store multiplicative inverses within the integers.

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Re:Arithmetic in Computer Hardware by nh23423fefe on Friday November 17, 2023 @03:41PM (#38309894)

I dunno if its "best" when compared to just regular old Z_(2^32)

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Re:Arithmetic in Computer Hardware by adgjlsfhk1 on Friday November 17, 2023 @07:49PM (#38313243)

Z_(2^32) is a really good explanation for unsigned integers, but to me at least it's not a great explanation of why signed integers are the way they are.

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Re:Arithmetic in Computer Hardware by nh23423fefe on Monday November 20, 2023 @01:42PM (#38352396)

But the justification is the same, congruence modulo 2^n

Z_4

     0  1  2  3  4  5  6  7  8  9 
     0  1  2  3  0  1  2  3  0  1
     0  1 -2 -1  0  1 -2 -1  0  1

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