Parity Definition and 220 Threads

A parity bit, or check bit, is a bit added to a string of binary code. Parity bits are a simple form of error detecting code. Parity bits are generally applied to the smallest units of a communication protocol, typically 8-bit octets (bytes), although they can also be applied separately to an entire message string of bits.
The parity bit ensures that the total number of 1-bits in the string is even or odd. Accordingly, there are two variants of parity bits: even parity bit and odd parity bit. In the case of even parity, for a given set of bits, the occurrences of bits whose value is 1 are counted. If that count is odd, the parity bit value is set to 1, making the total count of occurrences of 1s in the whole set (including the parity bit) an even number. If the count of 1s in a given set of bits is already even, the parity bit's value is 0. In the case of odd parity, the coding is reversed. For a given set of bits, if the count of bits with a value of 1 is even, the parity bit value is set to 1 making the total count of 1s in the whole set (including the parity bit) an odd number. If the count of bits with a value of 1 is odd, the count is already odd so the parity bit's value is 0. Even parity is a special case of a cyclic redundancy check (CRC), where the 1-bit CRC is generated by the polynomial x+1.
If a bit is present at a point otherwise dedicated to a parity bit but is not used for parity, it may be referred to as a mark parity bit if the parity bit is always 1, or a space parity bit if the bit is always 0. In such cases where the value of the bit is constant, it may be called a stick parity bit even though its function has nothing to do with parity. The function of such bits varies with the system design, but examples of functions for such bits include timing management or identification of a packet as being of data or address significance. If its actual bit value is irrelevant to its function, the bit amounts to a don't-care term.

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  1. N

    Engineering Minimum Hamming Distance for Parity Check Matrix

    My answer: Then, if I am not mistaken, the solution made in that video is mostly guessing about which columns combination can be equals to zero and I found 1st, 2nd, and 3rd rows as well as 2nd, 3rd, 4th rows are equals to zero so the minimum hamming distance is 3 since my answer is mostly...
  2. S

    Comp Sci Parity Check Question -- University Level Intro Course: Networking

    What I know: Parity check is used to detect if there are errors when transmitting data by adding redundancy bits to the dataword (data that we want to send) which creates a codeword. Then the receiver checks if the 1's are even or odd and based on that, we know that there was corruption during...
  3. H

    Kramers-Kronig, parity and delta function

    Hi, First of all, I'm not sure to understand what he Kramers-kronig do exactly. It is used to get the Real part of a function using the imaginary part? Then, when asked to add a peak to the parity at ##\omega = -\omega_0##, is ##Im[\epsilon_r(\omega)] = \delta(\omega^2 - \omega_0 ^2)## correct...
  4. guyvsdcsniper

    Using Parity operator for addition/subtraction

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  5. deme76

    Problem set with 5 proofs involving odd, even, parity, etc.

    help me in my problem set qs
  6. T

    MHB Parity: Show that the sum contains at least one even number.

    Hello, guys! I have a question that need help! A number with 17 digits is chosen and the order of its digits is inverted, forming a new number, These two numbers are then added up. Show that the sum contains at least one even number.
  7. ergospherical

    I Parity Selection Rules: I'm Confused

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  8. M

    I Parity Operator in 2D: Understanding Transformation & Spin

    Hello! What is the 2D (acting in spin space) representation of the parity operator. In principle we can make it a diagonal matrix with the right transformation and given that ##P^2=1## the matrix would be diag(1,1) or diag(1,-1). However spin shouldn't change under parity and using that it seems...
  9. W

    B Symmetry of parity: Mistake in the experiment?

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  10. B

    Help with Space Inversion Symmetry Problem

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  11. L

    A potential well with 3-fold reflection symmetry

    When we are talking about Bloch's theorem and also the tight-binding approximation, we can use them to help finding eigenstates of a system. However, I am so confused how to apply it in this case (below is my homework) and don't even know how to start it... All I understand about the Bloch's...
  12. L

    A Hamiltonian commutes with a parity operator -- What does that mean?

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  13. N

    I Parity Eigenstates: X Basis Explanation

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  14. mjmnr3

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  15. M

    I How can I prove the parity violation potential in a P,T-symmetric system?

    Hello! I read in several papers (e.g. this one) that if we have 2 levels of fixed, opposite parities, which are the eigenstates of a P,T-even Hamiltonian, and we add a perturbing potential which is P-odd, T-even, the matrix element of the new potential between the 2 states of opposite parity...
  16. M

    I Why Is Octupole Deformation Measurable in Nuclei but Not Dipole Deformation?

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  17. I

    A Predicting the positive parity and zero spin of the Higgs boson?

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  18. G

    Checking Parity Invariance of the QED Lagrangian

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  19. K

    I Parity and Interactions: Misreading or Misunderstanding?

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  20. A

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  21. F

    A G-parity - where does the minus sign come from?

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  22. Phylosopher

    B Why does parity give raise to pseudovectors?

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  23. M

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  24. J

    Initial states ppbar can proceed to npi^0 with parity conserved

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  25. D

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  26. renec112

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  27. Mr Davis 97

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  28. J

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  29. H

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  30. Gene Naden

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  31. Gene Naden

    I Pion decaying to two neutrons demonstrates odd parity

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  32. I

    I Vectors in Minkowski Space & Parity: Checking the Effect

    It is known that vectors change them sing under the influence of parity when ##(x,z,y)## change into ##(-x,-z,-y)## $$P: y_{i} \rightarrow -y_{i}$$ where ##i=1,2,3## But what about vectors in Minkowski space? Is it true that $$P: y_{\mu} \rightarrow -y_{\mu}$$ where ##\mu=0,1,2,3##. If yes how...
  33. I

    I Parity of theta term of Lagrangian

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  34. C

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  35. N

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  36. Diksha17

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  37. V

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  38. MaxFieg

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  39. D

    I Proof that parity operator is Hermitian in 3-D

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  40. nomadreid

    I Antimatter opposite parity to its matter partner?

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  41. V

    A How parity exchanges right handed and left handed spinors

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  42. D

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  43. J

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  44. T

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  45. Incnis Mrsi

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  46. M

    A How Does the Dirac Spin Exchange Operator Work in Quantum Mechanics?

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  47. J

    I How Is Spin and Parity Determined in Pion Decay?

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  48. M

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  49. P

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  50. I

    Nuclear shell model, spin and parity predictions

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