离散直方图刻画的正态分布

Question

我如何使用 tikz 生成以下图像？

我已经看到了绘制正态曲线的代码，但是如何让矩形形状在其中心处正对呢？红色不是那么重要。

Answer 1

随意注释...

\documentclass[tikz,border=5]{standalone}
\usepackage[eulergreek]{sansmath}
\usepackage{pgfplots}
\pgfplotsset{compat=newest,
  tick label style={font=\sansmath\sffamily},
  axis line style={draw=black!80, line width=0.1875ex},
  y tick label style={/pgf/number format/fixed},
  tick style={major tick length=0.0ex},
  major grid style={thick, dash pattern=on 0pt off 2pt, black!50},
}
\pgfmathdeclarefunction{norm}{3}{%
  \pgfmathparse{sqrt(0.5*#3/pi)*exp(-0.5*#3*(#1-#2)^2)}%
}
\begin{document}
\begin{tikzpicture}[line cap=round, line join=round]
\begin{axis}[ymajorgrids, xmajorgrids]
\addplot [ybar, domain=0:15, samples=16, fill=blue!50!cyan, draw=none] 
  (x, {norm(x, 7.5, 0.25)});
\addplot [very thick, draw=orange,  domain=0:15, samples=100, smooth]
  (x, {norm(x, 7.4, 0.25)});
\end{axis}
\end{tikzpicture}
\end{document}