MayaVi is a free, cross platform, easy-to-use scientific data visualizer. It provides a powerful GUI to ease the visualization process. It is written in Python and uses the Visualization Toolkit (VTK) for the graphics. MayaVi can be scripted from other Python programs and also from the interactive Python interpreter. MayaVi includes the VTK Pipeline browser. The VTK Pipeline browser is a Python module (vtkPipeline) that enables one to view and configure the objects in the VTK pipeline graphically with a Tkinter-based GUI. The browser should work for any Python script that uses VTK. MayaVi also provides classes to pickle a VTK object and a simple class documentation browser.
QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.
PyStem is a fast Python module with the the Porter stemming algorithm (a process for removing the commoner morphological and inflexional endings from words in English; its main use is as part of a term normalisation process that is usually done when setting up Information Retrieval systems).
arrayfrombuffer allows a programmer to use Numerical Python arrays whose contents are stored in buffer objects, including memory-mapped files. Loading an array from a file is easy, requiring only a module import and a single function call. Loading the array is quick because it doesn't require any copying from one part of memory to another. Arrays created with arrayfrombuffer are also highly memory-efficient, since only the array data that you are currently using gets loaded into memory. When an array is modified, only the modified parts get written back out to disk. These arrays can also be bigger than physical memory.
Python-mhash is a Python interface to the mhash library, which provides a uniform interface to a large number of hash algorithms. These algorithms can be used to compute checksums, message digests, and other signatures. The HMAC support implements the basics for message authentication, following RFC 2104.
Python-mcrypt is a comprehensive Python interface to the mcrypt library, which provides a uniform interface to several symmetric encryption algorithms. It is intended to have a simple interface to access encryption algorithms in ofb, cbc, cfb, ecb, and stream modes. It supports algorithms like DES, 3DES, RIJNDAEL, Twofish, IDEA, GOST, CAST-256, ARCFOUR, SERPENT, SAFER+, and more.
RPy is a very simple, yet robust, Python interface to the R Programming Language. It can manage all kinds of R objects and can execute arbitrary R functions (including the graphic functions). All the errors from the R language are converted to Python exceptions. Any module that later were installed on the R system can easily be used from within Python, without introducing any changes.