Graphics, Figures & Tables ⇒ Number Line Help

[tpa77l3]

Hey guys,

I'm completely new to LaTeX and have thrown myself somewhat in the deep end when starting a maths course.

I would like some help creating a number line with another line above it. The higher of the two lines requires dots on either end; one filled and one not. Example attached.

Any pointers would be greatly appreciated. Thanks in advance.

Screenshot 2020-02-24 at 20.06.44.png (35.01 KiB) Viewed 10386 times

[Bartman]

It should be easier for beginners to create the drawing with pgf/TikZ. My solution uses pgfplots:

Code: Select all

\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}

\begin{document}
\begin{tikzpicture}
\begin{axis}[
    x=3mm,
    axis y line=none,
    axis x line=center,
    xtick align=outside,
    xtick={-5,0,...,30},
    xmin=-7, xmax=33, 
    ymin=0, ymax=1,
    xlabel=$x$,
    xlabel style={anchor=north}
]
\addplot [nodes=draw, circle, inner sep=1.5pt] 
    coordinates {(-5,.1) (25,.1)} 
        node [fill, at start] {}
        node [fill=white] {}
;
\end{axis}
\end{tikzpicture}
\end{document}

A possible replacement for the command \addplot:

Code: Select all

\draw [nodes=draw, circle, inner sep=1.5pt]
    (-5,.1) node (filled) [fill] {}
    (25,.1) node (open) {}
    (filled) -- (open)
;

[tpa77l3]

This is perfect - thank you!

Just one more addition I need to may if you wouldn't mind. I need to include a label above the top line as below:

Screenshot 2020-02-25 at 05.50.46.jpg (27.29 KiB) Viewed 10365 times

[Bartman]

Code: Select all

\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}

\begin{document}
\begin{tikzpicture}[
    dot/.style={draw, fill=#1, circle, inner sep=1.5pt},
    filled/.style={dot},
    open/.style={dot=white}
]
\begin{axis}[
    x=3mm,
    axis y line=none,
    axis x line=center,
    xtick align=outside,
    xtick={-5,0,...,30},
    xmin=-7, xmax=33, 
    ymin=0, ymax=1,
    xlabel=$x$,
    xlabel style={anchor=north}
]
\addplot [black]
    coordinates {(-5,.1) (25,.1)} 
        node [filled, at start] {}
        node [open] {}
        node [above, midway] {A}
;
\end{axis}
\end{tikzpicture}
\end{document}

The other way:

Code: Select all

\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}

\begin{document}
\begin{tikzpicture}[
    dot/.style={draw, circle, inner sep=1.5pt},
    filled/.style={dot, fill},
    open/.style={dot}
]
\begin{axis}[
    x=3mm,
    axis y line=none,
    axis x line=center,
    xtick align=outside,
    xtick={-5,0,...,30},
    xmin=-7, xmax=33, 
    ymin=0, ymax=1,
    xlabel=$x$,
    xlabel style={anchor=north}
]
\draw
    (-5,.1) node [filled] (filled) {}
    (25,.1) node [open] (open) {}
    (filled) -- node [above] {A} (open)
;
\end{axis}
\end{tikzpicture}
\end{document}

[tpa77l3]

Much appreciated