Plotting an arbitrary function in latex

Question

I would like to know how I can replicate the diagram below in latex.

thanks.

Edit: I can plot a function using tikz/pgfplots if I know how the function is defined. Unfortunately, I don't know how the function is defined in this case.

Use pgfplots. See for example Easiest way to plot a function with PGF/TikZ. — Peter Grill, Apr 12 '14 at 19:00
Can you at least give the function that produces that graph? — Gonzalo Medina, Apr 12 '14 at 19:02
@GonzaloMedina There was no function. Well I guess the function is unknown. — Nana, Apr 12 '14 at 19:04
@Nana Well, you need to have some description of the function before you can plot anything. It seems that your question is more about maths (interpolation, approximation) than about plotting things in LaTeX... — jub0bs, Apr 12 '14 at 19:19
This question appears to be off-topic because it is more about how to derive a mathematical description for an unknown function than about actually plotting a function in LaTeX. The question may have to be migrated to Maths.SX. — jub0bs, Apr 12 '14 at 19:20
See also the hobby library by Andrew Stacey, which can be used to assemble a nice-looking curve if you can guess a few points on it. — Charles Staats, Apr 12 '14 at 19:43
@CharlesStaats You should post an answer using hobby. I'd never heard of before. Just been playing with it because of your comment. Never nice solution!! — A.Ellett, Apr 12 '14 at 20:12
I have a hobby solution I'll post if the hold on the question is removed. — DJJerome, Apr 12 '14 at 21:28

Gonzalo Medina · Accepted Answer · 2014-04-12T19:21:33.977

3

Using pgfplots you can do something like this:

\documentclass{article}
\usepackage{pgfplots}

\begin{document}

\begin{tikzpicture}
\begin{axis}[
  axis lines=middle,
  domain=-1:7,
  yticklabels=\empty,
  xtick={-1,...,7},
  xticklabels={-1,...,7},
  samples=100
  ]
\addplot[no markers] {-0.1*x*(x-3)*(x-3)*(x-6)};
\end{axis}
\end{tikzpicture}

\end{document}

enter image description here

Refer to the package documentation to adjust the settings according to your needs.

edited Apr 12 '14 at 19:21

answered Apr 12 '14 at 19:08

Gonzalo Medina

505,128

1

I did:
`\documentclass[english,a4paper,11pt,oneside]{article} \usepackage{tikz}

\begin{document}

\begin{tikzpicture}[domain=-.7:6.7,] \foreach \x/\xtext in {-1/-1, 1/1, 2/2, 3/3, 4/4, 5/5, 6/6, 7/7} \draw[shift={(\x,0)}] (0pt,2pt) -- (0pt,-2pt) node[below] {$\xtext$}; \draw[->] (-1.2,0) -- (7.2,0) node[right] {$x$}; \draw[->] (0,-6.2) -- (0,1.2) node[above] {$f(x)$}; \draw [samples=200] plot (\x,{-0.1\x(\x-3)(\x-3)(\x-6)}); \end{tikzpicture}

\end{document}`

and works well also. Sorry, I can't go to newline in comments...?
– MattAllegro Apr 13 '14 at 00:41

Plotting an arbitrary function in latex

1 Answers1