Tikz| How to change line color and style?

Question

I want to know how to change the color and the style of line in my graph, it's possible for marks but not for lines. this is my code :

    \begin{minipage}[b]{.48\linewidth}
    \begin{tikzpicture}[y=.1714cm, x=.5cm,font=\sffamily]
    %axis
    \draw (1,0) -- coordinate (x axis mid) (9,0);
    \draw (1,0) -- coordinate (y axis mid) (1,35);
  %ticks
  \draw (1.5,1pt) -- (1.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {20$\times$10};
    \draw (2.5,1pt) -- (2.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {20$\times$20};
    \draw (3.5,1pt) -- (3.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {40$\times$20};
    \draw (4.5,1pt) -- (4.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {40$\times$40};
    \draw (5.5,1pt) -- (5.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {60$\times$30};
    \draw (6.5,1pt) -- (6.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {60$\times$60};
    \draw (7.5,1pt) -- (7.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {80$\times$40};
    \draw (8.5,1pt) -- (8.5,-3pt) node[anchor=north, rotate = 45, above=-.7cm] {80$\times$80};
  \foreach \y in {2,6,10,14,18,22,26,30,34}
        \draw (0.9,\y) -- (1.1,\y) node[anchor=east] {\y}; 
    %labels      
    \node[below=1.5cm] at (x axis mid) {Instances};
    \node[rotate=90, left=1cm] at (y axis mid) {CPU time [in hundreds of seconds]};
    %plots
    \draw plot[mark=*, mark options={fill=white}] file {f_3_2.data};
    \draw plot[mark=triangle*, mark options={fill=black} ] file {q_3_2.data};
    %legend
    \begin{scope}[shift={(2,24)}] 
    \draw (0,0) -- 
        plot[dashed, mark=*, mark options={fill=white}] (0.25,0) -- (0.5,0) 
        node[right]{Algo. LOQ};
    \draw[yshift=\baselineskip] (0,0) -- 
        plot[mark=triangle*, mark options={fill=black}] (0.25,0) -- (0.5,0)
        node[right]{Algo. \cite{Ref9}};
    \end{scope}
\end{tikzpicture}

i get this :

when i try to change the lines color or style by the following code, it doesn't work and without catching errors :

\draw plot[style=dashed, draw=red, mark=*, mark options={fill=white}] file {f_3_2.data};

even the position of the coordinates label can't be changed !

Thank you for helping me.

Welcome to TeX.SE! Try \draw[<color>] ..... For your image is simpler to use pgfplots instead pure tikz. — Zarko, Jul 28 '21 at 13:56
Try this \draw[..., ultra thick, densely dashed, red] plot .... — fromthebeeland, Jul 28 '21 at 14:15
@Zarko Thanks for your welcome and your quick response. I try to work with pgfplots, but i did not find a clear documentation to do what i need (like the picture). With pure tikz, it's well unless the styles and colors. If you have a good documentation or a quick code, it will be a great help. Thanks — BADJARA Mohamed el Amine, Jul 28 '21 at 14:16
This link can be helpful, it's relevant to your question. https://tex.stackexchange.com/questions/105570/how-to-plot-functions-like-x-fy-using-tikz — fromthebeeland, Jul 28 '21 at 14:21

Zarko · Accepted Answer · 2021-08-04T12:38:34.600

I would rather use pgfplots package. It has extensive package manual, which is part of package installation or you can find in CTAN by googling for Manual for Package pgfplots.

An uncomplete example (since your data table is not known), can be:


\documentclass[border=3.141592]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\begin{document}
    \begin{tikzpicture}
\begin{axis}[
    axis lines = left,
    xtick = {0,1,...,9},
    xticklabels = { ,
                    $20\times10$, $20\times20$, $40\times20$, $40\times20$,
                    $60\times30$, $60\times60$, $80\times40$, $40\times80$},
    x tick label style = {rotate=45, anchor=east},
    xmin=0, xmax=9.5, xlabel = {instances},
    ymin=0, ymax=35,  ylabel={CPU time [in hundreds of seconds]},
    legend pos={north west},
every axis plot post/.append style={thick}
             ]%axis
\addplot coordinates { (1,2)  (2,6)  (3,10)
                       (4,14) (5,18) (6,22)
                       (7,26) (8,30) (9,34)};
\end{axis}
    \end{tikzpicture}
\end{document}

An example, how to use table of diagram's data, see this answer.

Tikz| How to change line color and style?

1 Answers1