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latex:example_projection

Example of adding and projecting vectors. For more, please visit https://tikz.net/category/physics/particle-physics/.

projection.tex
% Author: Izaak Neutelings (June 2017)

\documentclass{article}
\usepackage{amsmath}
\usepackage{tikz}
\tikzset{>=latex} % for LaTeX arrow head
\usetikzlibrary{calc} % to sum coordinates
\newcommand*{\vv}[1]{\vec{\mkern0mu#1}} % correct \vec misalignment

% split figures into pages
\usepackage[active,tightpage]{preview}
\PreviewEnvironment{tikzpicture}
\setlength\PreviewBorder{5pt}

\begin{document}

% PZETA VIS
\begin{tikzpicture}

% vector labels
\def\pT{ \vv{p}^\text{\tiny\,vis}_\text{\tiny\,T}}
\def\pTA{\vv{p}^\text{\tiny\,vis}_\text{\tiny\,T,1}}
\def\pTB{\vv{p}^\text{\tiny\,vis}_\text{\tiny\,T,2}}

% define point
\coordinate (O)  at (0.0, 0.0);
\coordinate (Z)  at (3.5, 0.0);
\coordinate (A)  at (1.0, 1.8);
\coordinate (B)  at (1.2,-2.16);
\coordinate (AB) at ($(A)+(B)$);
\path let \p{AB}=(AB) in coordinate (P) at (\x{AB},0); % projection

% axis
\draw[->,thick,dashed]
(-0.8,0) -- (Z)
node[at end,below] {$\vv{\zeta}$};

% main vectors
\draw[->,thick,color=red]
(O) -- (A)
node[below=4pt,left=4pt,color=red] {$\pTA$};
\draw[->,thick,color=red]
(O) -- (B)
node[above=2pt,left=2pt,color=red] {$\pTB$};
\draw[->,color=red]
(O) -- (AB)
node[below=4pt,right,color=red,scale=1] {$\pT$}; %{$\sq\pTA+\,\pTB$};

% helplines
\draw[dashed,color=red]
(A) -- (AB);
\draw[dashed,color=red]
(B) -- (AB);
\draw[dashed,color=purple]
(AB) -- (P);

% vector sum
\draw[->,thick,color=purple]
(O) -- (P)
node[right=4pt,above,color=purple] {$\vv{p}^\text{\tiny\,vis}_{\tiny\,\zeta}$};

\end{tikzpicture}

\end{document}
latex/example_projection.txt · Last modified: 2021/10/02 08:55 by iwn