1

I would like to be able to change the line style within a certain section of the graph given a single addplot command. Is there any way possible to change the properties of the line style for specified sections of the x axis? I have only seen similar Q&A addressing multiple addplots to fulfill the different line style and also a nice example in which it seems the solution is by adding a draw with a different style to meet the expectations of the question.. Though, it seems that it also just adds a different plot at the end plot visualization..

My MWE is shown below with an "ugly" solution of just splitting the sections as multiple addplot commands.

enter image description here

\documentclass[10pt,border=3mm,tikz]{standalone}
    \usepackage{pgfplots}
    \pgfplotsset{compat=1.18}
    \usetikzlibrary{pgfplots.groupplots}

\begin{document}
\begin{tikzpicture}   
        \begin{groupplot}[
            group style={
                group size = 1 by 1,
                },
            clip=true,
            enlargelimits=true,
            height = 0.75\columnwidth,
            width = 1\columnwidth,
            axis x line = center,
            axis y line = center,
            xlabel={$x$},
            xmin=0,
            xmax=3,
            xtick={0,1,2,3}
            ]
            \nextgroupplot[ymin=0,
                            ymax=10,
                            ytick={0,2,...,10},
                            ylabel = {$y$}
                            ]

                \addplot[color=blue, domain = 0:1, samples=50                   
                        ] {x^2};
                \addplot[color=blue, dashed, domain = 1:2, samples=50                   
                        ] {x^2};
                \addplot[color=blue, domain = 2:3, samples=50                   
                        ] {x^2};

        \end{groupplot}    
    \end{tikzpicture}
\end{document}

Thanks in advance.

MS-SPO
  • 11,519
otiuuaugusto
  • 51
  • 2
    Doesn't look like conditional styling or similar is implemented. But looks like you can try softclipping, see Ch. "5.5 Decoration: Soft Clipping" in the PGFPLOTSmanual. However, code won't become shorter ... or easier to understand ... – MS-SPO May 15 '23 at 15:00
  • You could maybe use a custom dash pattern, but it would require a lot of calculation. I would actually stick to your version. It is at least clean and easy to read. – Jasper Habicht May 15 '23 at 16:16

1 Answers1

3

You can make use of soft clip provided by the fillbetween library (as suggested by MS-SPO in the comments) and create your custom style inspired by the example on page 104 of the current PGFPlots manual (version 1.18.1):

\documentclass[border=10pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\usetikzlibrary{pgfplots.groupplots, fillbetween}

\pgfplotsset{
    dashed between/.style args={#1:#2}{
        draw=none,
        postaction={
            draw,
            decorate,
            decoration={
                soft clip,
                soft clip path={
                    (\pgfkeysvalueof{/pgfplots/xmin},\pgfkeysvalueof{/pgfplots/ymin}) rectangle
                    (#1,\pgfkeysvalueof{/pgfplots/ymax})
                },
            }
        },
        postaction={
            draw,
            dashed,
            decorate,
            decoration={
                soft clip,
                soft clip path={
                    (#1,\pgfkeysvalueof{/pgfplots/ymin}) rectangle
                    (#2,\pgfkeysvalueof{/pgfplots/ymax})
                },
            }
        },
        postaction={
            draw,
            decorate,
            decoration={
                soft clip,
                soft clip path={
                    (#2,\pgfkeysvalueof{/pgfplots/ymin}) rectangle
                    (\pgfkeysvalueof{/pgfplots/xmax},\pgfkeysvalueof{/pgfplots/ymax})
                },
            }
        }
    }
}


\begin{document}
\begin{tikzpicture}

    \begin{groupplot}[
        group style={
            group size=1 by 1,
        },
        clip=true,
        enlargelimits=true,
        height=0.75\columnwidth,
        width=1\columnwidth,
        axis x line=center,
        axis y line=center,
        xlabel={$x$},
        xmin=0,
        xmax=3,
        xtick={0,1,2,3}
    ]
    \nextgroupplot[
        ymin=0,
        ymax=10,
        ytick={0,2,...,10},
        ylabel={$y$}
    ]


    \addplot[color=blue, domain={0:3}, dashed between={1:2}] {x^2};

    \addplot[color=red, domain={0:3}, dashed between={0.5:2.5}] {4};

\end{groupplot}    



\end{tikzpicture}
\end{document}

enter image description here

Jasper Habicht
  • 48,848