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https://www.dropbox.com/s/0d1sh8pxn6savgm/IMG_20121005_010828.jpg

Scan from textbook

Can anyone identify the names of the crosshair and ^ symbols?

90% sure the ^ means bitwise AND from searching wikipedia, but I haven't found the crosshair symbol anywhere else.

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7  
^ is called caret, not carrot. –  Chris Eagle Oct 5 '12 at 8:17
2  
I was wondering who would draw a little carrot as an operator in a math equation. Perhaps a Bugs Bunny fan. –  Rahul Oct 5 '12 at 9:51
    
caret*** thanks! –  SwimBikeRun Oct 5 '12 at 16:04

1 Answer 1

up vote 5 down vote accepted

I take it that you’re asking about $\land$ and $\bigoplus$ in this displayed line:

$$\psi_i(x)=Y\left(\bigoplus_{k=0}^{L-1}\left(x[k]\land i[k]\right)\right)\qquad x,i\in\mathcal{B}^L$$

Judging from the context, $\mathcal{B}$ is probably $\{0,1\}$, so that $x$ and $i$ are $L$-bit bitstrings. If so, I expect that you’re right about $\land$: $0\land 0=0\land 1=1\land 0=0$, and $1\land 1=1$. $\bigoplus$ is almost certainly non-carrying addition, or if you prefer, exclusive OR: $0\oplus 0=1\oplus 1=0$, $0\oplus 1=1\oplus 0=1$, and $\bigoplus$ is related to $\oplus$ as $\sum$ is related to $+$.

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Great. Thank you –  SwimBikeRun Oct 5 '12 at 16:04

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