How do I draw a B+ tree in latex?

Question

Is there some way to draw a B+ tree in latex? It would look something like the picture below (ignoring the animations)

Animation linked here: http://i.stack.imgur.com/JRcmY.gif

Screenshot of the start of the animation:

Answer 1

I would do this in TikZ. Section 18.1 of the version 2.10 manual shows how to make trees. The nodes on the trees are a little nonstandard, but perhaps section 16.3 on multi-part nodes would be helpful.

Here's a quick mockup:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes}
\begin{document}
\begin{center}
\begin{tikzpicture}
\tikzstyle{bplus}=[rectangle split, rectangle split horizontal,rectangle split ignore empty parts,draw]
\tikzstyle{every node}=[bplus]
\tikzstyle{level 1}=[sibling distance=60mm]
\tikzstyle{level 2}=[sibling distance=15mm]
\node {15} [->]
  child {node {3 \nodepart{two} 7}
    child {node {1 \nodepart{two} 2}}
    child {node {4 \nodepart{two} 6}}
    child {node {8 \nodepart{two} 9}}    
  } 
  child {node {21 \nodepart{two} 28 \nodepart{three} 32 \nodepart{four} 50}
    child {node {17 \nodepart{two} 20}}
    child {node {22 \nodepart{two} 25}}
    child {node {28 \nodepart{two} 30}}    
    child[sibling distance=25mm] {node {34 \nodepart{two} 38 \nodepart{three} 44 \nodepart{four} 47}}    
    child[sibling distance=25mm] {node {53 \nodepart{two} 54 \nodepart{three} 60 \nodepart{four} 88}}    
  }
;\end{tikzpicture}
\end{center}

\end{document}

It's going to be more work to get the vertical lines doubled like in your example. The code for the rectangle split shape may need to be altered.

Answer 2

http://tug.org/PSTricks/main.cgi?file=pst-tree/pst-tree#binary can be modified to your needs