graphviz software package provides rich set of graph drawing tools, you can install in your Debian 7 (Wheezy) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install graphviz
graphviz is installed in your system.
Make ensure the graphviz package were installed using the commands given below,
$ sudo dpkg-query -l | grep graphviz *
You will get with graphviz package name, version, architecture and description in a table
| Distro | Debian 7 wheezy |
| Section | Graphics |
| Package | graphviz |
| Version | 2.26.3-14+deb7u2 |
| Description | rich set of graph drawing tools |
| Sub Section | Graphics |