This example shows how to draw a basic pie chart. Note that labels are automatically aligned and placed in a smart way. This makes the code more complicated. However, charts can now bee drawn without worrying about overlapping labels.

Edit and compile if you like:
% Pie chart% Author: Robert Vollmert\documentclass{article}\usepackage{calc}\usepackage{ifthen}\usepackage{tikz}\usepackage[active,floats,tightpage]{preview}\PreviewEnvironment{tikzpicture}\setlength\PreviewBorder{5pt}%\begin{document}\newcommand{\slice}[4]{\pgfmathparse{0.5*#1+0.5*#2}\let\midangle\pgfmathresult% slice\draw[thick,fill=black!10] (0,0) -- (#1:1) arc (#1:#2:1) -- cycle;% outer label\node[label=\midangle:#4] at (\midangle:1) {};% inner label\pgfmathparse{min((#2-#1-10)/110*(-0.3),0)}\let\temp\pgfmathresult\pgfmathparse{max(\temp,-0.5) + 0.8}\let\innerpos\pgfmathresult\node at (\midangle:\innerpos) {#3};}\begin{tikzpicture}[scale=3]\newcounter{a}\newcounter{b}\foreach \p/\t in {20/type A, 4/type B, 11/type C,49/type D, 16/other}{\setcounter{a}{\value{b}}
Click to download: pie-chart.tex • pie-chart.pdf
Open in Overleaf: pie-chart.tex