另一种可能性

Question

考虑下面的 MWE。蓝线在 上方延伸 -1。我们可以将 y 刻度移到 RH 侧吗y<0？怎么做？

\documentclass[a4paper]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\begin{document}

\begin{tikzpicture}
  \begin{axis}[
    xmin=-3.3,xmax=3.3,
    ymin=-1.4,ymax=1.4,
    axis x line=middle,    
    axis y line=middle, 
    ytick={-1,0,1},
    ]
     \addplot[thick,blue,domain=\pgfkeysvalueof{/pgfplots/xmin}:0,samples=2] {-1};
    \addplot[thick,red,domain=0:\pgfkeysvalueof{/pgfplots/xmax},samples=2] {1};
  \end{axis}
\end{tikzpicture}

\end{document}

Answer 1

您可以使用extra y tick-1，然后更改ticklabel style它的。

\documentclass[a4paper]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.14}
\begin{document}

\begin{tikzpicture}
  \begin{axis}[
    xmin=-3.3,xmax=3.3,
    ymin=-1.4,ymax=1.4,
    axis x line=middle,    
    axis y line=middle, 
    ytick={0,1},
    extra y ticks={-1},
    extra y tick style={tick label style={right=3pt}}
    ]
    \addplot[thick,blue,domain=\pgfkeysvalueof{/pgfplots/xmin}:0,samples=2] {-1};
    \addplot[thick,red,domain=0:\pgfkeysvalueof{/pgfplots/xmax},samples=2] {1};
  \end{axis}
\end{tikzpicture}
\end{document}

另一种可能性

警告：接下来是丑陋的黑客行为。

\documentclass[a4paper,border=4mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\begin{document}

\begin{tikzpicture}
  \begin{axis}[
    xmin=-3.3,xmax=3.3,
    ymin=-1.4,ymax=1.4,
    axis x line=middle,    
    axis y line=middle, 
    ytick={-1,0,1},
    yticklabel={%
      \ifdim\tick pt <0pt
        \rlap{\quad\axisdefaultticklabel}
      \else
         \axisdefaultticklabel
      \fi
    }
    ]
    \addplot[thick,blue,domain=\pgfkeysvalueof{/pgfplots/xmin}:0,samples=2] {-1};
    \addplot[thick,red,domain=0:\pgfkeysvalueof{/pgfplots/xmax},samples=2] {1};
  \end{axis}
\end{tikzpicture}
\end{document}