TikZ-Trees – Fixing Error Drawing Trees Using TikZ

tikz-pgftikz-trees

I'm trying to draw a tree with tikz

I've tried this:

\documentclass{report}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[nodes={draw, circle}]
\path
(0, 0)          node        (1a)        {5};
(-2, -1)        node        (2a)        {12};

\draw
(1a)--(2a)
\end{tikzpicture}
\end{document}

I get ! Package pgf Error: No shape named `2a' is known. How can I fix it?

I would also like to tweak the links.

If I omit the \draw part, only the first node is drawn. How can I draw 2 nodes without any link?

Is there any way to draw with a thicker line?

Best Answer

You are terminating the \path with a semicolon after making the 1a node but not starting a new path, so the second node invocation does nothing.

If you check the log the error is preceded by

Missing character: There is no ( in font nullfont!
Missing character: There is no - in font nullfont!
Missing character: There is no 2 in font nullfont!
Missing character: There is no , in font nullfont!
Missing character: There is no - in font nullfont!
Missing character: There is no 1 in font nullfont!
Missing character: There is no ) in font nullfont!
Missing character: There is no n in font nullfont!
Missing character: There is no o in font nullfont!
Missing character: There is no d in font nullfont!
Missing character: There is no e in font nullfont!
Missing character: There is no ( in font nullfont!
Missing character: There is no 2 in font nullfont!
Missing character: There is no a in font nullfont!
Missing character: There is no ) in font nullfont!
Missing character: There is no 1 in font nullfont!
Missing character: There is no 2 in font nullfont!
Missing character: There is no ; in font nullfont!

! Package pgf Error: No shape named `2a' is known.

indicating the (-2, -1) node (2a) {12}; line is trying to be printed rather than parsed.

You also need a semicolon to terminate the \draw command.

\documentclass{report}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[nodes={draw, circle}]
\path
(0, 0)          node        (1a)        {5}
(-2, -1)        node        (2a)        {12};

\draw
(1a)--(2a);
\end{tikzpicture}
\end{document}

Depending on your use case though

\documentclass{report}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[nodes={draw, circle}]
\node (1a) at (0, 0) {5};
\node (2a) at (-2, -1) {12};

\draw (1a)--(2a);
\end{tikzpicture}
\end{document}

might be easier to write.

Related Solutions

[Tex/LaTex] How to define the default vertical distance between nodes

I don't really get the question so I hope this is what you wanted. If you include a full document (such that we copy paste and see the problem on our systems) things are much more easier.

Here, you can change the default setting within a scope but your block style had a node distance which was resetting every time it is issued. I've made it 2mm such that we can see the difference easier.

\documentclass[tikz]{standalone}
\usetikzlibrary{arrows,shapes.geometric,positioning}

\begin{document}
\begin{tikzpicture}[decision/.style={diamond, draw, text width=4.5em, text badly centered, node distance=3.5cm, inner sep=0pt},
                    block/.style   ={rectangle, draw, text width=6em, text centered, rounded corners, minimum height=4em, minimum height=2em},
                    cloud/.style   ={draw, ellipse, minimum height=2em},
                    line/.style    ={draw,-latex'},
                    node distance = 1cm, 
                    auto]
    \node [block] (1st) {1st};
    \node [block, right= of 1st]  (2nd1) {2nd1};
\begin{scope}[node distance=2mm and 10mm]%Here we change it for everything inside this scope
    \node [block, above= of 2nd1] (2nd2) {2nd2};
    \node [block, below= of 2nd1] (2nd3) {2nd3};
    \node [block, right= of 2nd1] (3rd1) {3rd1};
    \node [block, above= of 3rd1] (3rd2) {3rd2};
    \node [block, above= of 3rd2] (3rd3) {3rd3};
\end{scope}
    \node [block, below= of 3rd1] (3rd4) {3rd4};
    \node [block, below= of 3rd4] (3rd5) {3rd5};

    \path [line] (1st) -- (2nd1);
    \path [line] (2nd1) -- (2nd2);
    \path [line] (2nd1) -- (2nd3);
    \path [line] (2nd2) -- (3rd3);
    \path [line] (2nd1) -- (3rd1);
    \path [line] (1st) -- (2nd1);
\end{tikzpicture}
\end{document}

enter image description here

[Tex/LaTex] Numerical conditional within tikz keys

I am definitely unfamiliar with both beamer and tikz (do not quite get what the \only are supposed to do) but perhaps this could go in the direction you want:

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{chains}
\newcounter{count}

% helper macro:
\long\def\GobToSemiColon #1;{}

\newcommand\myPicture{
\begin{tikzpicture}
  \begin{scope}[start chain = going below]
  \ifnum\value{count}<1 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>3 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is between
    1 and 3};

  \ifnum\value{count}>-1 \expandafter\GobToSemiColon\fi
  \node[draw, rectangle, on chain] {display only when counter is
    negative}; 

  \ifnum\value{count}<100 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>200 \expandafter\GobToSemiColon\fi  
  \node[draw, rectangle, on chain] {display only if counter is between
    100 and 200};

  \ifnum\value{count}<3 \expandafter\GobToSemiColon\fi
  \ifnum\value{count}>20 \expandafter\GobToSemiColon\fi
  \node[draw, circle, on chain] {only when counter is in the range 3 to 20};
  \end{scope}
\end{tikzpicture}
}

\begin{document}
\begin{frame}
\only{\setcounter{count}{-3}\myPicture}
\only{\setcounter{count}{105}\myPicture}
\only{\setcounter{count}{39}\myPicture}
\only{\setcounter{count}{2}\myPicture}
\only{\setcounter{count}{5}\myPicture}
\end{frame}
\end{document}

beamer

Best Answer

Related Solutions

[Tex/LaTex] How to define the default vertical distance between nodes

[Tex/LaTex] Numerical conditional within tikz keys

Related Question