Logarithmic plot using tikz ung pgfplots

Question

I want to draw a logarithmic plot of wavelength and frequency. The x and y axes show an exponential plot. I want the representation to be a simple number. How do I change the labels on the axes?

Since the wavelength λ = c/f

the graph should get along without a data set, because one end value and one start value of the equation should be enough. How do you realize something like this?

c = speed of light = 299792458 m/s

I have added an example in the appendix.

\documentclass{article}
\usepackage{mwe}
\usepackage{pgfplots}
\usepackage{siunitx}
\begin{document}
    \begin{tikzpicture}
    \begin{axis}[
    width=0.9\textwidth,
    title=Umrechnung Frequenz in Wellenlänge,
    xlabel={Frequenz $f$ [\unit{\MHz}]},
    ylabel={Wellenlänge $\lambda$ [\unit{\m}]},
    xmin=0, xmax=1000,
    ymin=0, ymax=300,
    domain=0:1000,
    restrict y to domain=0:300,
    grid=both
    ]
    \end{axis}
    \end{tikzpicture}
\end{document}

Please convert you code snippet to a compilable minimal working example (MWE) in order to help others help you. — Jasper Habicht, Sep 08 '22 at 11:21

Rmano · Answer 1 · 2022-09-08T12:31:31.790

Hmmm...

log axis can't start from 0.
\[ ... \] is a command for displayed math, not a square bracket. Use square brackets when needed
You must give a \pgfplotsset{compat...} to avoid surprises
package mwe is not for MWEs (yeah, I know...)
why limiting y?
Adjust the formula, I just put 300/x to put something there.

\documentclass{article}
\usepackage{pgfplots}\pgfplotsset{compat=1.18}
\usepackage{siunitx}
\begin{document}
\begin{tikzpicture}
    \begin{loglogaxis}[
        width=0.9\textwidth,
        title=Umrechnung Frequenz in Wellenlänge,
        xlabel={Frequenz $f$ [\unit{\MHz}]},
        ylabel={Wellenlänge $\lambda$ [\unit{\m}]},
        xmin=1, xmax=1000,
        ymin=1, ymax=300,
        domain=1:1000,
        log basis y  = 10,
        grid=both
        ]
        \addplot [thick, blue] {300/x};
    \end{loglogaxis}
\end{tikzpicture}
\end{document}

See also pgfplots: How can I customize number formatting styles for log plots based on the numbers? , pgfplots ticklabel format logarithmic scale , and log plot with fixed number format on one axis

Logarithmic plot using tikz ung pgfplots

1 Answers1