172

Taking from the PGF manual,

\begin{tikzpicture}
  \draw [help lines] (0,0) grid (3,3);
  \coordinate (a) at (rnd,rnd);
  \coordinate (b) at (3-rnd,3-rnd);
  \draw (a) -- (b);
  \node (c) at (1,2) {x};
  \draw let \p1 = ($ (a)!(c)!(b) - (c) $),
            \n1 = {veclen(\x1,\y1)}
        in circle [at=(c), radius=\n1];
\end{tikzpicture}

I'd like to increase the size of x. The problem is that I have multiple circles in the same diagram. Some of them require a larger sized font, while others are okay at default. How do I do this?

Qrrbrbirlbel
  • 119,821
TheRealFakeNews
  • 5,537

4 Answers4

249

You can change the font size inside a tikZ node like you do it in normal LaTeX – use one of these:

\tiny
\scriptsize
\footnotesize
\small
\normalsize
\large
\Large
\LARGE
\huge
\Huge

e.g.

\node (c) at (1,2) {\large x};

or

\node (c) at (1,2) {\large $x$}; %note the \large *outside* the inline math

Edit: To change font size inside math mode, LaTeX provides the following commands:

\displaystyle
\textstyle
\scriptstyle
\scriptscriptstyle

Using scaling algorithms provided by tikZ/pgf (e.g. scale=...) scales "the entire character", so it may look ugly if you use too much scaling. If you set the font sizes with the above commands, LaTeX selects different symbols for the different font sizes. This ensures the fonts are readable and have enough "details". If you want a more extreme scaling, use the scale=3.0 option for the node.

Peater de Xel
  • 4,859
  • it says it's invalid with math mode? – TheRealFakeNews Apr 05 '13 at 17:53
  • 11
    Maybe worth pointing out the font key which could be of help in this case :) – Claudio Fiandrino Apr 05 '13 at 17:56
  • 1
    @ralfix sorry i didn't mention it. it's too early in the morning for me. bah! – TheRealFakeNews Apr 05 '13 at 18:02
  • 1
    @ClaudioFiandrino: Do you mean the scale option? – Peater de Xel Apr 05 '13 at 18:11
  • 36
    @Qrrbrbirlbel: you're right... what I wanted to say was that \node (c) at (1,2) {\large x}; is equivalent to \node[font=\large] (c) at (1,2) {x}; – Claudio Fiandrino Apr 05 '13 at 19:15
  • 13
    @ClaudioFiandrino: with the notable exception that {\large x\\y} produces a large x and a normal y, while \node[font=\large,align=center] {x\\y} makes everything large. – Michaël Dec 07 '16 at 14:15
  • See this post for discussion on scaling inside math mode – Brett Mar 20 '18 at 22:50
  • 1
    @ClaudioFiandrino I would like to note that for multi-line text there is a difference between \node at (...) [font=\small, text width=1cm]{A long text ...}; and \node at (...) [text width=1cm] {\small A long text ...}; regarding the line spacing. In the first case, the line spacing is adjusted, in the second it is not. The line break is also different. – Michael.H Apr 21 '22 at 09:17
  • @Michael.H: Absolutely right, and the same applies to Michaël's observation. Indeed my example was with one character only and does not generalize to something more complex. – Claudio Fiandrino Apr 21 '22 at 09:29
58

Set a new style so that you can use it later.

For example:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{calc}
\usepackage{relsize}

\tikzset{fontscale/.style = {font=\relsize{#1}}
    }

\begin{document}
\begin{tikzpicture}
  \draw [help lines] (0,0) grid (3,3);
  \coordinate (a) at (rnd,rnd);
  \coordinate (b) at (3-rnd,3-rnd);
  \draw (a) -- (b);
  \node (c) at (1,2) [fontscale=4] {x};
  \draw let \p1 = ($ (a)!(c)!(b) - (c) $),
            \n1 = {veclen(\x1,\y1)}
        in circle [at=(c), radius=\n1];
\end{tikzpicture}
\end{document}
cacamailg
  • 8,405
27

At the top, write

\begin{tikzpicture}[thick,scale=1, every node/.style={scale=1.3}]
\draw [help lines] (0,0) grid (3,3);
\coordinate (a) at (rnd,rnd);
\coordinate (b) at (3-rnd,3-rnd);
\draw (a) -- (b);
\node (c) at (1,2) {x};
\draw let \p1 = ($ (a)!(c)!(b) - (c) $),
        \n1 = {veclen(\x1,\y1)}
    in circle [at=(c), radius=\n1];
\end{tikzpicture}

the thick changes your arrows, the first scale changes the scale of your drawing, but the second argument changes the size of your nodes, presumably where you have your text. This will change for all nodes.

Jimmy TwoCents
  • 391
17

You can use the font option of the \node command. The font option accepts typical font commands such as \node[font = {\Huge\bfseries\sffamily}, red] (huge font size, bold, sans serif).

enter image description here

(Taken from the manual.)

enter image description here

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{calc}


\begin{document}


\begin{tikzpicture}
  \draw [help lines] (0,0) grid (3,3);
  \coordinate (a) at (rnd,rnd);
  \coordinate (b) at (3-rnd,3-rnd);
  \draw (a) -- (b);
  \node[font = {\normalfont}, red] (c) at (1,2) {x}; % <=== See here!
  \draw let \p1 = ($ (a)!(c)!(b) - (c) $),
            \n1 = {veclen(\x1,\y1)}
        in circle [at=(c), radius=\n1];
\end{tikzpicture}


\begin{tikzpicture}
  \draw [help lines] (0,0) grid (3,3);
  \coordinate (a) at (rnd,rnd);
  \coordinate (b) at (3-rnd,3-rnd);
  \draw (a) -- (b);
  \node[font = {\Huge\bfseries\sffamily}, red] (c) at (1,2) {x}; % <=== See here!
  \draw let \p1 = ($ (a)!(c)!(b) - (c) $),
            \n1 = {veclen(\x1,\y1)}
        in circle [at=(c), radius=\n1];
\end{tikzpicture}


\end{document}


\tiny
\scriptsize
\footnotesize
\small
\normalsize 
\large
\Large

\LARGE

\huge

\Huge

enter image description here

(Taken from the manual.)

Dr. Manuel Kuehner
  • 22,451