如何在不向网格添加新线的情况下添加额外的刻度

Question

我需要在 x 轴上添加一个额外的刻度，而不在新的 x 值处添加新的网格线，问题是我使用额外的刻度来获得完整的网格（这是在这个邮政) 其中线的起点和终点位于 x 轴和 y 轴的整数边界处。

\documentclass[border=3mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
    axis lines=center,
    grid=major,
    grid style={dotted, cyan},
    anchor=origin,
    xlabel = $x$, ylabel =$y$,  % Set the labels
    xmin= -4, xmax= 4,
    ymin=-4, ymax=4,
    xtick={-3,-2,...,3},
    ytick={-3,-2,...,3},
    extra x ticks={-4,3.14, 4},
    extra y ticks={-4, 4},
    extra tick style={grid=major, grid style={dotted, cyan}},
    extra x tick labels={,\hspace{.4em}$\pi$,},
    extra y tick labels={},
    color=cyan
]
\end{axis}
\end{tikzpicture}
\end{document}

Answer 1

要添加extra tickx 轴，您可以使用

extra x tick style={grid=none},

在选项中：

\documentclass[border=3mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
    axis lines=center,
    grid=major,
    grid style={dotted, cyan},
    anchor=origin,
    xlabel = $x$, ylabel =$y$,  % Set the labels
    xmin= -4, xmax= 4,
    ymin=-4, ymax=4,
    xtick={-3,-2,...,3},
    ytick={-3,-2,...,3},
    extra x ticks={-4,3.14, 4},
    extra y ticks={-4, 4},
    extra tick style={grid=major, grid style={dotted, cyan}},
    extra x tick labels={,\hspace{.4em}$\pi$,},
    extra y tick labels={},
    extra x tick style={grid=none}, %% <<-----
    color=cyan
]
\end{axis}
\end{tikzpicture}
\end{document}

这将使 x 轴两侧的最后网格线消失，可以使用以下方法绘制

\draw[dotted,cyan] (4,-4) -- (4,4)
                   (-4,-4) -- (-4,4);
\end{axis}

以下是 Gonzalo 提到的手动绘图选项：

\documentclass[border=3mm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.12}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
    axis lines=center,
    grid=major,
    grid style={dotted, cyan},
    anchor=origin,
    xlabel = $x$, ylabel =$y$,  % Set the labels
    xmin= -4, xmax= 4,
    ymin=-4, ymax=4,
    xtick={-3,-2,...,3},
    ytick={-3,-2,...,3},
    extra x ticks={-4, 4},
    extra y ticks={-4, 4},
    extra tick style={grid=major, grid style={dotted, cyan}},
    extra x tick labels={},%,\hspace{.4em}$\pi$,},
    extra y tick labels={},
    %extra x tick style={grid=none}, %% <<-----
    color=cyan
]
 \draw[very thin,gray] (3.14,0.1) -- (3.14,-0.1)node[anchor=north west,inner xsep=0pt,text=cyan] {$\pi$};
\end{axis}
\end{tikzpicture}
\end{document}