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AeroCalc AeroCalc is a python package that performs various aeronautical engineering calculations. Currently, it contains the following main modules:

• airspeed
• default_units
• ssec
• std_atm
• unit_conversion

Asymptote 'Asymptote' is a script-based vector graphics language for technical drawing, inspired by MetaPost but with an improved C++-like syntax. It provides for figures the same high-quality level of typesetting that LaTeX does for scientific text. It is a programming language, not just a graphics program, so it can use the best features of both scripts and GUIs. High-level graphics commands are implemented in the language itself, so they can be tailored to specific applications. Labels and equations are typeset with LaTeX for high-quality PostScript output.

Avogadro Avogadro is an advanced molecule editor and visualizer designed for cross-platform use in computational chemistry, molecular modeling, bioinformatics, materials science, and related areas. It offers flexible high quality rendering and a powerful plugin architecture.

• International: Translations into Chinese, French, German, Italian, Russian, Spanish, and others, with more languages to come.
• Intuitive: Built to work easily for students and advanced researchers both.
• Fast: Supports multi-threaded rendering and computation.
• Extensible: Plugin architecture for developers, including rendering, interactive tools, commands, and Python scripts.
• Flexible: Features include Open Babel import of chemical files, input generation for multiple computational chemistry packages, crystallography, and biomolecules.

BKchem BKchem is a chemical drawing program written in Python. It is platform independent.

Biskit Biskit is a python library for structural bioinformatics research. It simplifies the analysis of macromolecular structures, protein complexes, and molecular dynamics trajectories and offers a platform for the rapid integration of external programs.

BlockCanvas The BlockCanvas project provides a visual environment for creating simulation experiments, where function and data are separated. Thus, you can define your simulation algorithm by visually connecting function blocks into a data flow network, and then run it with various data sets (known as "contexts"); likewise, you can use the same context in a different functional simulation. The project provides support for plotting, function searching and inspection, and optimization. It includes a stand-alone application that demonstrates the block-canvas environment, but the same functionality can be incorporated into other applications. The BlockCanvas project relies on included libraries that allow multiple data sets using Numeric arrays to be incorporated in a Traits-based model in a way that is simple, fast, efficient, and consistent.

CAGE A generic and fairly complete cellular automata simulation engine. CAGE is a fairy generic and complete cellular automaton simulation engine in Python. It supports both 1D and 2D automata, a variety of prepackaged rules, and the concept of "agents" which can move about independently on the map for implementing agent behavior. CAGE comes with numerous examples of fully-functional CA systems, including Conway's Game of Life, Langton's self-reproducing automaton, Langton's "vants," and 1D automata rule explorers. It also comes with simple displayers (including a curses interface for 2D automata). Also included is a unique implementation of a finite state machine (ant.py).

CCVisu The tool CCVisu is a light-weight tool for force-directed graph layout. The tool reads the input graph from a file in RSF (Rigi Standard Format), which is a standard text format for relations. The layout of the graph is computed using standard techniques from force-directed layout. The tool supports several energy models, which can be selected by setting command line parameters. The weighted edge-repulsion LinLog energy model (default) is good for producing layouts that fulfill certain clustering criteria. The Fruchterman Reingold energy model is good for producing layouts that fulfill certain esthetic criteria like uniform edge length. CCVisu stores the resulting layout in certain text file formats such as VRML or SVG, or it displays the layout on the screen.

CERTI CERTI is an HLA RTI. HLA (High-Level Architecture) is a general purpose architecture for distributed computer simulation systems. In HLA systems, the RTI (RunTime Infrastructure) manages data exchange between simulations. CERTI focuses on HLA 1.3 specification and its C++ API (IEEE 1516 will be supported too).

Chaco Chaco is a software for partitioning graphs mainly intended for parallel computing and scientific simulations. It implements a set of algorithms for this task ranging from a generalization of KL/FM with weighted graphs support to the premiere multilevel algorithms which combine high quality partitioning schemes and low computational costs.