使用 ymin 和 ymax 缩放刻度

Question

为了发表一篇文章，我正在用 PGFPlots 准备多个图，并希望它们看起来都一样，即具有相同的轴和相同的刻度。为此，我打算使用ymin和ymax，但 PGFPlots 似乎不尊重scaled ticks=true。

我试图将其归结为下面这个相当简单的例子，展示设置不同参数的效果。我想实现右下角的图，但是和缩放刻度。我做错了什么？

\documentclass{article}
\usepackage{pgfplots}
        \pgfplotsset{compat=newest,width=6cm}
\usepackage[pdftex,active,tightpage]{preview}
\begin{document}
    \begin{preview}
        \begin{tikzpicture}
            \begin{axis}[ title=Nothing ]
                \addplot [red] coordinates { (0,0.0003) (1,0.0004) };
            \end{axis}
        \end{tikzpicture}
        \begin{tikzpicture}
            \begin{axis}[ title={Scaled Ticks \emph{false}},
                    scaled ticks=false  ]
                \addplot [green] coordinates { (0,0.0003) (1,0.0004) };
            \end{axis}
        \end{tikzpicture}
        \begin{tikzpicture}
            \begin{axis}[ title={Scaled ticks \emph{true} with ymax},
                    scaled ticks=true,
                    ymax=0.0005 ]
                \addplot [blue] coordinates { (0,0.0003) (1,0.0004) };
            \end{axis}
        \end{tikzpicture}
        \begin{tikzpicture}
            \begin{axis}[ title={Scaled ticks \emph{true} with ymax \& ymin},
                    scaled ticks=true,
                    ymax=0.0005,
                    ymin=0 ]
                \addplot [cyan] coordinates { (0,0.0003) (1,0.0004) };
            \end{axis}
        \end{tikzpicture}
    \end{preview}
\end{document}

Answer 1

这似乎是 PGFPlots 中的一个错误（更新2012 年 1 月 22 日：这现已修复): 每当轴的最小值或最大值正好为 0 时，就不会应用缩放。您可以修补内部宏来检查并解决此问题。

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=newest,width=6cm}

%
\makeatletter
\def\pgfplots@init@scaled@tick@for#1{%
    \global\def\pgfplots@glob@TMPa{0}%
    \expandafter\pgfplotslistcheckempty\csname pgfplots@prepared@tick@positions@major@#1\endcsname
    \ifpgfplotslistempty
        % we have no tick labels. Omit the tick scale label as well!
    \else
    \begingroup
    \ifcase\csname pgfplots@scaled@ticks@#1@choice\endcsname\relax
    % CASE 0 : scaled #1 ticks=false: do nothing here.
    \or
        % CASE 1 : scaled #1 ticks=true:
        %--------------------------------
        % the \pgfplots@xmin@unscaled@as@float  is set just before the data
        % scale transformation is initialised.
        %
        % The variables are empty if there is no datascale transformation.
        \expandafter\let\expandafter\pgfplots@cur@min@unscaled\csname pgfplots@#1min@unscaled@as@float\endcsname
        \expandafter\let\expandafter\pgfplots@cur@max@unscaled\csname pgfplots@#1max@unscaled@as@float\endcsname
        %
        \ifx\pgfplots@cur@min@unscaled\pgfutil@empty
            \edef\pgfplots@loc@TMPa{\csname pgfplots@#1min\endcsname}%
            \expandafter\pgfmathfloatparsenumber\expandafter{\pgfplots@loc@TMPa}%
            \let\pgfplots@cur@min@unscaled=\pgfmathresult
            \edef\pgfplots@loc@TMPa{\csname pgfplots@#1max\endcsname}%
            \expandafter\pgfmathfloatparsenumber\expandafter{\pgfplots@loc@TMPa}%
            \let\pgfplots@cur@max@unscaled=\pgfmathresult
        \fi
        %
        \expandafter\pgfmathfloat@decompose@E\pgfplots@cur@min@unscaled\relax\pgfmathfloat@a@E
        \expandafter\pgfmathfloat@decompose@E\pgfplots@cur@max@unscaled\relax\pgfmathfloat@b@E
        \ifnum\pgfmathfloat@a@E=0%
            \pgfmathfloat@a@E=\pgfmathfloat@b@E%
        \fi%
        \ifnum\pgfmathfloat@b@E=0%
            \pgfmathfloat@b@E=\pgfmathfloat@a@E%
        \fi%
        \ifnum\pgfmathfloat@b@E<\pgfmathfloat@a@E%
            \pgfmathfloat@b@E=\pgfmathfloat@a@E%
        \fi
        \xdef\pgfplots@glob@TMPa{\pgfplots@scale@ticks@above@exponent}%
        \expandafter\ifnum\pgfplots@glob@TMPa<\pgfmathfloat@b@E
            % ok, scale it:
            \multiply\pgfmathfloat@b@E by-1
            \xdef\pgfplots@glob@TMPa{\the\pgfmathfloat@b@E}%
        \else
            \xdef\pgfplots@glob@TMPa{\pgfplots@scale@ticks@below@exponent}%
            \expandafter\ifnum\pgfplots@glob@TMPa>\pgfmathfloat@b@E
                % ok, scale it:
                \multiply\pgfmathfloat@b@E by-1
                \xdef\pgfplots@glob@TMPa{\the\pgfmathfloat@b@E}%
            \else
                % no scaling necessary:
                \xdef\pgfplots@glob@TMPa{0}%
            \fi
        \fi
    \or
        % CASE 2 : scaled #1 ticks=base 10:
        %--------------------------------
        \c@pgf@counta=\csname pgfplots@scaled@ticks@#1@arg\endcsname\relax
        %\multiply\c@pgf@counta by-1
        \xdef\pgfplots@glob@TMPa{\the\c@pgf@counta}%
    \or
        % CASE 3 : scaled #1 ticks=real:
        %--------------------------------
        \pgfmathfloatparsenumber{\csname pgfplots@scaled@ticks@#1@arg\endcsname}%
        \global\let\pgfplots@glob@TMPa=\pgfmathresult
    \or
        % CASE 4 : scaled #1 ticks=manual:
        \expandafter\global\expandafter\let\expandafter\pgfplots@glob@TMPa\csname pgfplots@scaled@ticks@#1@arg\endcsname
    \fi
    \endgroup
    \fi
    \expandafter\let\csname pgfplots@tick@scale@#1\endcsname=\pgfplots@glob@TMPa%
}
\makeatother
%

\begin{document}
\begin{tikzpicture}
    \begin{axis}[ title={Scaled ticks \emph{true} with ymax \& ymin},
        scaled y ticks=true,
        ymax=0.0008, ymin=0
    ]
        \addplot [cyan, domain=0:10] {0.0001*x};
    \end{axis}
\end{tikzpicture}
\end{document}