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My professor uses these symbols to formalize logic operators. I found versions of (a) and (b), which are rotated by 90°. For (c) I found \Finv, but it is not exactly the same and is also rotated by 90°.

I looked for the symbols in symbol collections on the web, but couldn't find exact representations. Does anyone know the LaTeX symbol codes for the shown symbols? I would like to avoid rotating the symbols manually.

Greets

Seminom

logic symbols

a) logical "and"
b) logical "or"
c) logical negation

COTO
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Seminom
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    Welcome to TeX.SE! – Mensch Apr 27 '21 at 14:01
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    Did your professor type those symbols, or write them on black board? (If the former, you can ask the professor; if the latter, they look like that they are intended to be "blackboard bold" versions. You may be able to just use \pmb or \boldsymbol on \land, \lor, and \neg to get actual bold version.) – Willie Wong Apr 27 '21 at 14:32
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    Try the compreensive symbol list. Of course there are versions without double rules like you ask. Search for \wedge, \vee and \neg in that list. – Miguel V. S. Frasson Apr 27 '21 at 14:35
  • @WillieWong he uses a PDF file, which he uses for years, but he is one of these persons who don't use computers very good. I guess someone created the file which he uses for the course. Currently he writes for demonstrations the symbols on the black board instead of the whiteboard which Zoom provides. But you're right, I could ask him. – Seminom Apr 27 '21 at 20:19
  • @MiguelV.S.Frasson Your provided link is not available. Just to let you know. I will try to find this document via google search. Thank you as well. – Seminom Apr 27 '21 at 20:24
  • @Mensch Thanks / Danke! :-) – Seminom Apr 27 '21 at 20:24
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    @Seminom, try http://mirrors.ctan.org/info/symbols/comprehensive/symbols-a4.pdf – Miguel V. S. Frasson Apr 28 '21 at 14:55

2 Answers2

4

I suggest making your own symbols:

enter image description here

\documentclass{article}

\usepackage{amssymb}
\usepackage{graphicx}


\newcommand{\AND}{\mathbin{\raisebox{.08ex}{\rotatebox[origin=c]{-90}{$\leqslant$}}}}
\newcommand{\OR}{\mathbin{\raisebox{.08ex}{\rotatebox[origin=c]{-90}{$\geqslant$}}}}
\newcommand{\NOT}{\lnot\hspace{-.5em}\lnot}


\begin{document}


$P\AND Q\land R$


$P\OR Q\lor R$


$\NOT P, \lnot P$


\end{document}
Sandy G
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3

I've never seen those symbols, except for one similar to your last one in a question here.

Rotating symbols seems the only way, but we can leave all calculations to TeX and not guess amounts of raising or lowering.

\documentclass{article}
\usepackage{amsmath,amssymb,graphicx}

\makeatletter
\newcommand{\qand}{\mathbin{\mathpalette\and@or@q\leqslant}}
\newcommand{\qor}{\mathbin{\mathpalette\and@or@q\geqslant}}


\newcommand{\and@or@q}[2]{%
  \vcenter{\hbox{%
    \raisebox{\depth}{\rotatebox[origin=c]{-90}{$\m@th#1#2$}}%
  }}%
}


\newcommand{\qnot}{\lnot\mspace{-9mu}\lnot}
\makeatother


\begin{document}


$\qnot x\qand y\qor z$


$\lnot x\land y\lor z$


\end{document}

enter image description here

egreg
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  • I have never seen these symbols before, too. It looks like, that it is special in my philosophy course. Thank you for your guideline. – Seminom Apr 27 '21 at 20:33
  • The characters look like "blackboard bold" versions of \vee, \wedge, and \neg, but I don't find those in the usual \Bbb fonts... – Eric Towers Apr 27 '21 at 22:39