Jolt Awards: Coding Tools, January 28, 2014 The best IDEs and coding tools of the past 12 months
Productivity Award: IPython Notebook
IPython notebook is the ultimate exploratory development environment. It describes itself as "a Web-based interactive computational environment where you can combine code execution, text, mathematics, plots, and rich media into a single document." Indeed, it is an open source Web application (running locally) that takes the power of IPython (built on top of Python with batteries included) and adds rich text, inline visualization and mathematical expressions. The combination enables creating live documents that you refine incrementally.
The interface is based on cells. Each cell can contain Python code, markdown text, or raw text. You can run, edit, and re-run each cell. Finally, you can save your work in a .ipynb file for later (which is just a JSON file you can store in source control), share it with the world via the notebook viewer service, or export it to a variety of other formats. I am a long-time Python user, but I never took to interactive sessions in the Python REPL. Even for interactive sessions, I often needed to write little functions and import modules from the complex systems I was working on. In the REPL (and even in IPython, which is much better), every typo ends up polluting the screen with long stack traces, which make the stuff you just typed in disappear from the screen. My solution was to write little exploratory test programs inside the IDE. IPython notebook's killer feature is the run-in-cell command, which lets you correct mistakes and re-run, erasing the previous output. IPython is an essential tool for any serious Python developer and even more so for beginners and weekend warriors.