Stack Overflow
Stack Overflow

Questions tagged [ones-complement]

The ones' complement of a numerical value is evaluated by performing a bitwise NOT operation on its binary representation.

The ones' complement of a numerical value is evaluated by performing a NOT operation on its binary representation.

Read also the wikipedia article on Ones' Complement.

91 questions
2
votes
1 answer

1's complement to 2's complement conversion

My code is a class for converting decimal to binary. it will display the binary, one's complement and two's complement. So far I have figured out the one's complement but having a problem finding a solution for the two's complement. my plan was to…
tms777
  • 35
  • 1
  • 5
2
votes
2 answers

Converting Decimal to Two's-Complement

Instructions: Convert these decimal numbers to 5-bit 2's-complement form, if possible. If not possible, explain why this is so. (16) base 10 According to the online converter: From what I understand, If decimal is positive: STEP 1: Convert…
k_rollo
  • 5,304
  • 16
  • 63
  • 95
1
vote
0 answers

What is the correlation between the nth and (n-1)th carry bit being equal and unequal and overflow occuring in the 1's or 2's complement sum

I recently found a problem in which the reason for overflow was that the carry bits were unequal. Is that a valid reasoning for overflow in binary arithmetic ? I saw that some other reasons for overflow were adding two negatives and getting a…
user16477826
  • 11
  • 4
1
vote
1 answer

Optimal bit twiddling for the One's complement absolute value operation on modern x86 processors

The fastest way to compute the absolute value of a twos complement number is a common enough operation that optimized implementations are widely available. So let's consider another case. What if we want to get the absolute value of a one's…
saolof
  • 1,097
  • 1
  • 15
  • 12
1
vote
1 answer

What does -1 in the solution of this code mean? Why is xor with -1 equivalent to a bitwise invert / not?

Provide a minimal set of RISC-V instructions that may be used to implement the following pseudoinstruction: not x5, x6 // bit-wise invert solution: xori x5, x6, -1
Mee
  • 13
  • 3
1
vote
0 answers

Express bitwise negation (`NOT`, bitwise complement) using other bitwise operations?

I am writing an algorithm in a limited language where the bitwise operators at my disposal are AND: & OR: | XOR: ^ SRL: << (shift left) SLL: >> (shift right) I realized I need to be able to take the bitwise complement of an integer, commonly…
bp99
  • 338
  • 3
  • 15
1
vote
0 answers

How to perform Arithmetic on Ones Complement Numbers and correct overflow?

For some backstory, I'm making a program that can do arithmetic on ones complement numbers. To do this I'm converting a binary string into a BigInteger and then performing the math using said BigIntegers, and then converting that back into a binary…
Talon Brown
  • 127
  • 13
1
vote
3 answers

Which complement does C use internally?

Everything I look up just tells me how to do complement operations/calculations in C. I want to know what representation does C use internally and how does it handle with overflow.
Miguel M
  • 302
  • 3
  • 16
1
vote
3 answers

What is the difference between -1 and ~0

The title really says it all: what is the difference between minus one and tilda (ones-complement) zero? The question came up during a discussion of the best way to specify a bit mask in which all bits are set. Which of the following is better? int…
zennehoy
  • 6,405
  • 28
  • 55
1
vote
2 answers

Type casting ~0 to (unsigned int) and (unsigned short) with format specifier %d and %u produces same result for short but different result for int

On my way to computing ranges of char, short, int, and long variables, both signed and unsigned, I took help of the following…
Haslo Vardos
  • 322
  • 2
  • 10
1
vote
1 answer

Confusion with 1's compliment binary representation

I was trying to learn binary representation of negative numbers. I tried to output 12 and ~12 in binary. print(~12) Output: -13 This was the 1's complement of 12. But my doubt is that binary 12 is 1100 and -13 (1's complement of 12) is 0011 but 3…
Gaurav
  • 333
  • 1
  • 16
1
vote
0 answers

One's Complement Arithmetic n C

I was trying to calculate the checksum of a UDP datagram in C. In order to calculate the UDP checksum, you create a pseudo header, prefix it to the datagram, and then compute the 16 bit one's complement of the one's complement sum of the pseudo…
user9583381
1
vote
1 answer

Can a floating Point System with 2's or 1's Complements Mantissa be Normalized?

As I understand a normalized mantissa is a fractional mantissa in which it's more significant bit, the one that equals 1/2, is always 1. And this is done in order to avoid repeated representations of the same number on the system. But what happens…
sir psycho sexy
  • 780
  • 7
  • 19
1
vote
2 answers

Why is 128 in one and two's complement using 8 bits overflow?

Suppose I want to represent 128 in one and two's complement using 8 bits, no sign bit Wouldn't that be: One's complement: 0111 1111 Two's complement: 0111 1110 No overflow But the correct answer is: One's complement: 0111 1111 Two's complement: 0111…
James Mitchell
  • 2,387
  • 4
  • 29
  • 59
1
vote
2 answers

R, Complement on aggregating data.table

Is it possible to aggregate with a complement in R data.tables. Example below. library(data.table) dt <- data.table(a=c("word1","word2","word2","word2"), b=c("cat1","cat1","cat1","cat2")) To get number of particular words in a category newdt <-…
puslet88
  • 1,288
  • 15
  • 25
1 2
3
4 5 6 7