Both internal and external vertex labels in the package tkz-graph?

Question

I'm drawing graphs in which I want to label vertices (e.g. x, y, z, w, etc), but also attach the value of a function calculated at each vertex (e.g. 4, -3, 2, 7 corresponding to vertices x, y, z, w etc). I'd like to achieve this by having x inside the vertex and the value of the function on the outside, though if there are other ways of achieving this easily I'd be open to that.

Is it possible to use the tkz-graph package to achieve this? I have read the documentation and (notwithstanding that my French is very rusty), I haven't been able to figure this out. Also open to alternative (simple & easy) packages that would allow me to achieve this.

(My level of LaTeX is $< \epsilon$)

\documentclass[10pt,border=3mm,tikz]{standalone}
\usepackage{tkz-graph}
\begin{document}
 \begin{tikzpicture}
    \GraphInit[vstyle=Normal]
    \SetGraphUnit{2}
    \SetVertexMath
    \Vertex{x}
    \Vertex[LabelOut, L=$4$, Lpos=90]{x} % this just replaces the internal label doesn't add an outside label
    \EA(x){y}
    \NOEA(y){z}
    \SOEA(z){w}
    \Edges(x,y,z,w,y,z) 
 \end{tikzpicture}
\end{document}

Answer 1

Here is one way to do it: mixing tkz-graph (built on Tikz) with plain Tikz.

Some hints

Tikz needs a semicolon ; at each end of a line to know "this path shall finish here". Think of a path being a series of commands to be executed, which we perceive as "drawing something". tkz-graph already provides this ; internally, so you can write them without this indicator. (And you can also mix both approaches.)

So in the first part just draw your structure with tkz-graph:

    \Vertex{x}      % default position: at (0,0)
    \EA     (x){y}  % EAst of x
    \NOEA   (y){z}  % NOrthEAst of y
    \SOEA   (z){w}  % SOuthEAst of z
\Edges(x,y,z,w,y,z) 

To place your labels just use ordinary \nodes from Tikz, like so:

• place a \node
• at the coordinate from (x), previously defined
• and put as text { }
• some Latex-compliant text, here in math mode $4$
• and finish this path, i.e. this single command, by ;

    % ~~~ and now some ordinary Tikz to place text in math mode $ $ ~~~
    %     kindly watch the semicolon ; needed here
    \node[abv]  at (x) {$4$};
    \node[bel]  at (y) {$-3$};
...

The styles abv and bel are defined in the beginning, and just shift the label a bit up and down, i.e. into y-direction. (Perhaps it's also available as a shortcut in tkz-graph.)

 \begin{tikzpicture}[   % defining some own styles
    abv/.style={yshift=6mm},
    bel/.style={yshift=-6mm},
 ]
...

Final results

\documentclass[10pt,border=3mm,tikz]{standalone}
\usepackage{tkz-graph}
\begin{document}
 \begin{tikzpicture}[   % defining some own styles
    abv/.style={yshift=6mm},
    bel/.style={yshift=-6mm},
 ]
    \GraphInit[vstyle=Normal]
    \SetGraphUnit{2}
    \SetVertexMath
\Vertex{x}      % default position: at (0,0)
\EA     (x){y}  % EAst of x
\NOEA   (y){z}  % NOrthEAst of y
\SOEA   (z){w}  % SOuthEAst of z

\Edges(x,y,z,w,y,z) 

% ~~~ and now some ordinary Tikz to place text in math mode $ $ ~~~
%     kindly watch the semicolon ; needed here
\node[abv]  at (x) {$4$};
\node[bel]  at (y) {$-3$};
\node[abv]  at (z) {$2$};
\node[bel]  at (w) {$7$};

\end{tikzpicture}
\end{document}