I recently asked the logical and character in TeX and got \land as the answer. My question is, why \land, and why not simple \and? I mean, does l here refer to something technical, or historical, or stuff like that? Or is it simply there to prevent name clash. Do we have \and in TeX?
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raphink
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Saeed Neamati
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The names are the same that Knuth gave them in Plain TeX. Since \or and \not are already used for more important things, adding the prefix l for "logical" was almost natural, so "and" followed the convention. And LaTeX continues with it.
The symbols \land, \lor and \lnot have synonyms: \wedge, \vee and \neg as they are called, I guess, by some lattice theory specialists.
egreg
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1Wedge is also the more natural name in algebra and geometry: http://en.wikipedia.org/wiki/Wedge_product – Caramdir Jul 22 '11 at 16:06
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1@Caramdir: some topologists use http://en.wikipedia.org/wiki/Wedge_sum, which unfortunately is often denoted using
\vee, not\wedge. – John Palmieri Jul 22 '11 at 18:53 -
1Even logicians use 'wedge' and 'vee' if they want to refer to the symbol rather than the connective it symbolises. Some systems use different symbols to represent the sane connectives (e.g. a dot for and or an ampersand). It is confusing, though, especially since there are no
\...forms for other connectives. (In practice,\landand\lorare not as important as\lifthen, for example. But\lifthenis unfortunately non-existent.) Wouldn't say 'neg', though. – cfr Aug 09 '15 at 22:54
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I think "l" stands for logical. I read \land as "logical and".
There's also \lor (which I read as "logical or") and \lnot (which I read as "logical not").
N.N.
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lstands for "logic" presumably. For\landit might not be a problem, but\oris a TeX primitive (I think) so\loris necessary to avoid that clash. – Seamus Jul 22 '11 at 12:02\andis already taken as well. At least inside\author. – You Jul 22 '11 at 12:07