http://www.python.org/

Excellent Object-Oriented Script Language for Engineering Research, Flexibility, Reusability, Dynamic, Release your creativity!

http://www.scipy.org/

Abundant numeric computing packages for fast prototyping of your algorithms

http://www.sagemath.org/

Do you need a complete package for replacing MATLAB?

http://learnhvac.org/index.php

Very cool simulation tool for understanding how HVAC system works, and how to make them work better

http://www.paraview.org/

Got a lot of data huhh? Can we visualize them and interprete them in a more ituitive way?

http://google-opensource.blogspot.com/2008/07/check-out-mox-our-mock-object-framework.html

If you are tired with writing a lot of codes to just test a small piece of code, try to mock those objects interacting with your code!

http://kepler-project.org/

Look at this! We can automate the data processing and interpretation procedure in a general way, and provide engineers and scientists a way to capture what they did for their data. For next step, maybe machine can learn these workflows automatically and become intelligent assistants of us!

http://code.enthought.com/projects/mayavi/

The best python 3D visualization package I have ever seen, especially for visualizing 3D points, but do not expect it is better than MATLAB plot3(), at least for now.

http://ipython.scipy.org/moin/

A combined set of powerful tools for running and debugging Python code iteractively, good command history support, variable saving support, macro creation and running, and a lot more.

http://pyparsing.wikispaces.com/

Simple module for creating simple grammars and parse tuples created using that grammar.

http://code.google.com/p/pydot/

Clean and elegant iterface for you to use GraphViz inside python, you can visualize Graphs (such as function calling stacks, workflows, class diagrams)

Python parsing tools

http://nedbatchelder.com/text/python-parsers.html

A good collection of python parsing tools.

http://www.pythoncad.org/

2D CAD environment implemented in Python.

http://www.ruby-lang.org/en/

Excellent script language, similar to Python, and is claimed to be more "Object-Oriented". Someone who are not comfortable with Python's "indent-based" sytax, and who prefer more explicit representation of private attributes, will find Ruby a better Python. However, Ruby is younger than Python, and it does not have so many open-source scientific packages implemented in Ruby as in Python yet.

http://simpy.sourceforge.net/

Discrete event simulation tool implemented in Python. Test your ideas about construction activities and processes by simulating it!

http://www.eso.org/sci/data-processing/software/scisoft/

A collection of RPM packages for scientific research, designed for astronomial research. It is an internally complete system (close world like MATLAB and SAGE). Enabling these internally integrated packaged to know externally available libraries, you need to spend sometime to understand ESO's packaging approach. You need to download the whole package (hundreds of RPM packages) and install them so that you do not have to worry about the complicated interdependency relationship between all those packages.

http://pyml.sourceforge.net/

From the author's webpage: "PyML is an interactive object oriented framework for machine learning written in Python. PyML focuses on SVMs and other kernel methods. "

http://yorick.sourceforge.net/index.php

From Yorick Webpage: Yorick is an interpreted programming language for scientific simulations or calculations, postprocessing or steering large simulation codes, interactive scientific graphics, and reading, writing, or translating large files of numbers. Yorick includes an interactive graphics package, and a binary file package capable of translating to and from the raw numeric formats of all modern computers.

Python Computer Graphics Kit

http://cgkit.sourceforge.net/

From the project introduction: "The Python Computer Graphics Kit is an Open Source software package containing a collection of Python modules, plugins and utilities that are meant to be useful for any domain where you have to deal with 3D data of any kind, be it for visualization, creating photorealistic images, Virtual Reality or even games."

http://rlabplus.sourceforge.net/

From the project abstract: "Project rlabplusis a continuation of work on an open-source scripting environment for scientific computations RLaB2. Project rlabplus provides release 2 of RLaB2, which contains upgrades of the numerical libraries used in the first release, and many new libraries and toolkits, e.g., Gnu Scientific Library (GSL)."

http://euler.sourceforge.net/

From the Euler project description: "EULER is a program for quickly and interactively computing with real and complex numbers and matrices, or with intervals, in the style of MatLab, Octave,... It can draw and animate your functions in two and three dimensions."

http://www.gnu.org/software/octave/

A open-source MATLAB clone trying to be compatible with MATLAB. Many m codes can be run in Octave without substantial changes.

http://www.scilab.org/

Another MATLAB-like scientific computing environment, it provides tools for translating M-code to SciLab code.

http://yacas.sourceforge.net/homepage.html

From project description: "YACAS is an easy to use, general purpose Computer Algebra System, a program for symbolic manipulation of mathematical expressions."

http://networkx.lanl.gov/

A Python package providing tools for analyzing and visualizing complicated network.

Python Imaging Library (PIL)

http://www.pythonware.com/products/pil/

Image Processing Toolbox Implemented in Python

http://www.ntu.edu.sg/home5/pham0004/pycv/

The name tells us everything: a package for fast training of face detection algorithms.

http://pyrorobotics.org/

A collection of python modules for conducting robotics research.

http://code.google.com/p/pyswip/

Symbolic reasoning package linking Python with SWI-Prolog

Natural Language Toolkit

http://www.nltk.org/

Natual language processing package, you can use it to explore ideas like automatic interpretation of natural language based construction documents.

http://jpype.sourceforge.net/

This interface between Java and Python integrates two virtual machines (Python and Java) rather than implementing Pythong using Java, and it has many benefits: access all CPython packages (Jypthon can not), faster running speed.

http://gnudatalanguage.sourceforge.net/

From GDL webpage: A free IDL (Interactive Data Language) compatible incremental compiler (ie. runs IDL programs). IDL is a registered trademark of ITT Visual Information Solutions.

Processing Environment

http://processing.org/learning/

Implemented in Java, this is a very flexible macro language system for you to interactively visualize and explore your large amounts of data.

http://www.zotero.org/

It is not just a tool for organizing research resources, it can be used to organize any documents, codes, figures for your research, excellent multi-view of your electronic resources, I will not use Explorer and File folders to organize my stuffs anymore.

http://www.heystaks.com/

Store your search queries, view your search history, organize your search queries, share your queries with you friends. Sharing searching results so that you do not have to search it again when you forgot how you find them from Internet, social search enable a group of people to do more powerful search results sharing: not just search results, but also the search history, and the correlations between queries.

Open Source Engineering Tools

http://wiki.developspace.net/Open_Source_Engineering_Tools

A DevelopSpace project for collecting useful opensource packages for engineers.

http://pypi.python.org/pypi/Shapely/

A Python package based on GEOS library for 2D geometric operations, currently used in GIS domain, but has potential for CAD mdel querying, spatial information retrieval as well.

http://theory.stanford.edu/~amitp/yapps/

From Ubuntu package description: YAPPS is an easy to use parser generator that is written in Python and generates Python code. There are several parser generator systems already available for Python, but this parser has different goals: Yapps is simple, very easy to use, and produces human-readable parsers.

http://matplotlib.sourceforge.net/

A python library for generating nice 2D figures similar as thoese generated by MATLAB, but the sytax of plotting commands are more flexible than m language.

Matplotlib Basemap Toolkit

http://matplotlib.sourceforge.net/basemap/doc/html/

Descriptions from its webpage: The matplotlib basemap toolkit is a library for plotting 2D data on maps in Python. It is similar in functionality to the matlab mapping toolbox, the IDL mapping facilities, GrADS, or the Generic Mapping Tools.

http://www.ctcms.nist.gov/fipy/

From the introductory webpage: FiPy is an object oriented, partial differential equation (PDE) solver, written in Python , based on a standard finite volume (FV) approach. The framework has been developed in the Metallurgy Division and Center for Theoretical and Computational Materials Science (CTCMS), in the Materials Science and Engineering Laboratory (MSEL) at the National Institute of Standards and Technology (NIST).

http://pyx.sourceforge.net/

From PyX website: PyX is a Python package for the creation of PostScript and PDF files. It combines an abstraction of the PostScript drawing model with a TeX/LaTeX interface. Complex tasks like 2d and 3d plots in publication-ready quality are built out of these primitives.

2D and 3D Graphics in Python

http://vermeulen.ca/python-graphics.html

A web site collecting python 2D and 3D graphics packages.

http://pyqwt.sourceforge.net/

From PyQwt webpage: PyQwt is a set of Python bindings for the Qwt C++ class library which extends the Qt framework with widgets for scientific and engineering applications. It provides a widget to plot 2-dimensional data and various widgets to display and control bounded or unbounded floating point values.

http://meshlab.sourceforge.net/

MeshLab is an open source, portable, and extensible system for the processing and editing of unstructured 3D triangular meshes.

http://code.enthought.com/projects/envisage/

From Envisage website: Envisage is a Python-based framework for building extensible applications, that is, applications whose functionality can be extended by adding "plug-ins". Envisage provides a standard mechanism for features to be added to an application, whether by the original developer or by someone else. In fact, when you build an application using Envisage, the entire application consists primarily of plug-ins. In this respect, it is similar to the Eclipse and Netbeans frameworks for Java applications.

http://pyevolve.sourceforge.net/

From the Pyevolve webpage: Pyevolve was developed to be a complete genetic algorithm framework written in pure python.

http://www.ailab.si/orange/

From Orange Site: Python open source data visualization and analysis for novice and experts. Data mining through visual programming or Python scripting. Extensions for bioinformatics and text mining. Comprehensive, flexible and fast.

http://rpy.sourceforge.net/

From RPy website: RPy is a very simple, yet robust, Python interface to the R Programming Language.

http://www.pymvpa.org/index.html

From PyMVPA website: PyMVPA is a Python module intended to ease pattern classification analyses of large datasets.

http://repast.sourceforge.net/

From RePast website: Repast Simphony is a free and open source agent-based modeling toolkit that simplifies model creation and use.

http://www.knime.org/

From KNIME website: the user-friendly and comprehensive open-source data integration, processing, analysis, and exploration platform.

http://codespeak.net/pypy/dist/pypy/doc/index.html

From PyPy web page: The PyPy project aims at producing a flexible and fast Python implementation. The guiding idea is to translate a Python-level description of the Python language itself to lower level languages. Rumors have it that the secret goal is being faster-than-C which is nonsense, isn't it?