`\documentclass[a4paper,11pt]{book}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[italian]{babel}
\usepackage{pgfplots}
\pgfplotsset{compat=newest,%
/pgf/number format/.cd,%
use comma,
fixed,
precision=4}
\begin{document}
\centering
\begin{tikzpicture}
\begin{axis}[ylabel={$\Delta$P (\%)},%
ymin=0,%
ymax=0.008,%
xtick=data,%
ymajorgrids=true,%
xtick pos=left,%
xticklabel style={rotate=90,anchor=east},%
xticklabel interval boundaries,%
symbolic x coords={$Test\,1$,$Test\,2$,$Test\,3$,$Test\,4$,$0$},%
scaled ticks={false}]
\addplot[ybar interval,fill=cyan, draw=black, bar width=0.2cm]
coordinates
{($Test\,1$, 0.003) ($Test\,2$, 0.003)
($Test\,3$, 0.002) ($Test\,4$, 0.007) ($0$, 0)};
\end{axis}
\end{tikzpicture}
\end{document}`Fai attenzione alle opzioni passate a pgfplots.
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