pgfplots 图表标签太近且间距不均匀

Question

我有一组数字作为 x 坐标：{2.08, 2.09, 2.7, 4.9, 12.8, 29.3, 64.2}。图的左侧部分太紧，因为2.08和2.09非常接近。我想均匀地将数字集分布在 x 轴上。可能吗？怎么做？请参见以下示例：

\begin{figure}[!h]
  \centering
      \caption{The example.}
      \label{figure:the_example}
      \begin{tikzpicture}[scale=0.45]
        \begin{axis}[ybar,xtick=data,xlabel=$ \lambda $,ylabel=$ \alpha $,
                      x tick label style={rotate=-35,anchor=west},width=2.2\textwidth,
                      height=0.32\textheight,legend pos=north west,ymin=0]
          \addplot coordinates {
            (2.08,10)
            (2.09,15)
            (2.7,25)
            (4.9,22)
            (12.8,21)
            (29.3,12)
            (64.2,17)
          };
        \end{axis}
      \end{tikzpicture}
\end{figure}

Answer 1

您可以使用symbolic x coords：

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.7}
\begin{document}
\begin{tikzpicture}[scale=0.45]
\begin{axis}[
  ybar,
  xlabel=$\lambda$,ylabel=$\alpha$,
  symbolic x coords={2.08,2.09,2.7,4.9,12.8,29.3,64.2},
]
\addplot coordinates {
  (2.08,10)
  (2.09,15)
  (2.7,25)
  (4.9,22)
  (12.8,21)
  (29.3,12)
  (64.2,17)
};
\end{axis}
\end{tikzpicture}
\end{document}