当 xmin 非零时，网格线无法正常显示

Question

我想\draw (0,0) grid[xstep=1,ystep=1] (5,5)在轴环境中这样做，但除非 xmin（和 ymin）为零，否则输出不会如预期。如何为这三个示例绘制 xstep 为 1 的网格？

注意：我想使用 \draw 中的网格命令，而不是 \axis 的网格选项或使用 \foreach 绘图。

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\begin{document}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=-1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=-1$},
    ]
    \draw (0,0) grid[xstep=1,ystep=1] (5,5);
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=0, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=0$},
    ]
    \draw (0,0) grid[xstep=1,ystep=1] (5,5);
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=1$},
    ]
    \draw (0,0) grid[xstep=1,ystep=1] (5,5);
  \end{axis}
\end{tikzpicture}

% This works as expected.
\newcommand{\DrawGrid}{
  \draw\foreach\k in {0,1,...,5} {(\k,0) -- (\k,5) (0,\k) -- (5,\k)};
}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=-1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=-1$},
    ]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=0, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=0$},
    ]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=1$},
    ]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\end{document}

这是输出：第一行是实际输出，第二行是预期输出。

Answer 1

使用pgfplots step来自我的答案似乎按预期工作。

代码

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\tikzset{pgfplots step/.style args={#1 by #2}{step={(axis direction cs:#1,#2)}}}
\begin{document}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=-1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=-1$}]
    \draw (0,0) grid[pgfplots step=1 by 1] (5,5);
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=0, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=0$}]
    \draw (0,0) grid[pgfplots step=1 by 1] (5,5);
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=1$}]
    \draw (0,0) grid[pgfplots step=1 by 1] (5,5);
  \end{axis}
\end{tikzpicture}

% This works as expected.
\newcommand{\DrawGrid}{
  \draw\foreach\k in {0,1,...,5} {(\k,0) -- (\k,5) (0,\k) -- (5,\k)};
}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=-1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=-1$}]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=0, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=0$}]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\begin{tikzpicture}
  \begin{axis}[
      width=12em, height=12em, xmin=1, xmax=7, ymin=0, ymax=7,
      xlabel={$x_\mathrm{min}=1$}]
    \DrawGrid
  \end{axis}
\end{tikzpicture}
\end{document}

输出