2
$\begingroup$

I've seen this function M2 = tmp ⊕ Pi. What does the circle with cross do?

  • 0
    The article calculated hash functions. tmp is a hash value and Pi is a random secret2012-12-05

2 Answers 2

9

In logic and CompSci, $\oplus$ is used to denote the "exclusive or" or "XOR": $\quad x \lor y \land \lnot(x \land y)$.

In set theory, $\oplus$ denotes the disjoint union.

In linear algebra/vector analysis, it's used to denote the direct sum of two vector spaces.

It's also used to denote parity: see P Parity.


Clearly, the context in which it's used is crucial.


In $LaTeX$: use \oplus.

0

$\oplus$ is often used for Directed Sum.

In Computer Science(especially cryptography), $\oplus$ usually means XOR, or bitwise addition.

  • 1
    Ok I think they meant XOR. Beause the article I read about was about cryptography2012-12-05