Spyder: A MATLAB-like IDE

Spyder is the Scientific PYthon Development EnviRonment:

a powerful interactive development environment for the Python language with advanced editing, interactive testing, debugging and introspection features;
and a numerical computing environment thanks to the support of IPython (enhanced interactive Python interpreter) and popular Python libraries such as NumPy (linear algebra), SciPy (signal and image processing) or matplotlib (interactive 2D/3D plotting).

Spyder websites:

Downloads, bug reports and feature requests: https://github.com/spyder-ide/spyder
Discussions: http://groups.google.com/group/spyderlib

Key features of Spyder:

General features:

matlab-like PYTHONPATH management dialog box (works with all consoles)
Windows only: current user environment variables editor
direct links to documentation (Python, Matplotlib, !NumPy, !Scipy, etc.)
direct link to Python(x,y) launcher
direct links to !QtDesigner, !QtLinguist and !QtAssistant (Qt documentation)

Preferences dialog box:

keyboard shortcuts
syntax coloring schemes (source editor, history log, help)
console: background color (black/white), automatic code completion, etc.
and a lot more...

Editor (Spyder's text editor is a multi-language editor with features such as syntax coloring, code analysis (real-time code analysis powered by pyflakes and advanced code analysis using pylint), introspection capabilities such as code completion, calltips and go-to-definition features (powered by rope), function/class browser, horizontal/vertical splitting features, etc.):

syntax coloring (Python, C/C++, Fortran)
breakpoints and conditional breakpoints (debugger: pdb)
run or debug Python scripts (see console features)
run configuration dialog box:

working directory
command line options
run in a new Python interpreter or in an existing Python interpreter or IPython client
Python interpreter command line options

code outline explorer: functions, classes, if/else/try/... statements
powerful code introspection features (powered by rope):

code completion
calltips
go-to-definition: go to object (any symbol: function, class, attribute, etc.) definition by pressing Ctrl+Left mouse click on word or Ctrl+G (default shortcut)

occurrence highlighting
typing helpers (optional):

automatically insert closing parentheses, braces and brackets
automatically unindent after 'else', 'elif', 'finally', etc.

to-do lists (TODO, FIXME, XXX)
errors/warnings (real-time code analysis provided by pyflakes)
integrated static code analysis (using pylint)
direct link to winpdb external debugger

Console:

all consoles are executed in a separate process
code completion/calltips and automatic link to help (see below)
open Python interpreters or basic terminal command windows
run Python scripts (see source editor features)
variable explorer:

GUI-based editors for a lot of data types (numbers, strings, lists, arrays, dictionaries, ...)
import/export data from/to a lot of file types (text files, !NumPy files, matlab files)
multiple array/list/dict editor instances at once, thus allowing to compare variable contents
data visualization

I. Installation

Spyder is quite easy to install on Windows, Linux, and MacOS X. Just read the following instructions with care.

1. Installing on Windows

Spyder is already included in these Python Scientific Distributions:

You can start using it immediately after installing one of them (you only need to install one!). You can install Spyder and its dependencies by running this command:
pip install spyder

Updating Spyder

You can update Spyder by:

Updating Anaconda, WinPython or Python(x,y).
Or using this command (in case you don't use any of those scientific distributions):

pip install --upgrade spyder

2. Installing on MacOS X

There are two alternatives:

Use the Anaconda Python distribution.
Use our DMG installers, which can be found here.

3. Installing on Linux

Ububtu:
- Using the official package manager sudo apt-get install spyder
- Using the pip package manager:
Debian:
Using the package manager: sudo apt-get install spyder
The Spyder's official Debian package is available here.
Other Distributions:
Spyder is also available in other GNU/Linux distributions.

II. Editor

Spyder's text editor is a multi-language editor with features such as syntax coloring, code analysis (real-time code analysis powered by pyflakes and advanced code analysis using pylint), introspection capabilities such as code completion, calltips and go-to-definition features (powered by rope), function/class browser, horizontal/vertical splitting features, etc.

How to define a code cell

A "code cell" is a concept similar to matlab's "cell" (except that there is no "cell mode" in Spyder), i.e. a block of lines to be executed at once in the current interpreter (Python or IPython). Every script may be divided in as many cells as needed.
Cells are separated by lines starting with:

#%% (standard cell separator)
# %% (standard cell separator, when file has been edited with Eclipse)
# <codecell> (IPython notebook cell separator)

IPython Console

Spyder's IPython Console implements a full two-process IPython session where a lightweight front-end interface connects to a full IPython kernel on the back end. Visit the IPython project website for full documentation of IPython's many features.

From the Consoles menu, Spyder can launch IPython Console instances that attach to kernels that are managed by Spyder itself or it can connect to external kernels that are managed by IPython Qt Console sessions or the IPython Notebook.

When "Connect to an existing kernel" is selected, Spyder prompts for the kernel connection file details:

IPython Consoles that are attached to kernels that were created by Spyder support the following features:

Code completion
Variable explorer with GUI-based editors for arrays, lists, dictionaries, strings, etc.
Debugging with standard Python debugger (pdb): at each breakpoint the corresponding script is opened in the Editor at the breakpoint line number
User Module Deleter (see Console for more details)

Debugging

Debugging in Spyder is supported thanks to the following Python modules:

pdb: the Python debugger, which is included in Python standard library.
winpdbw: a graphical frontend to pdb, which is an external package (in the Editor, press F7 to run winpdb on the currently edited script).

Console

The Console is where you may enter, interact with and visualize data, inside a command interpreter. All the commands entered in the console are executed in a separate process, thus allowing the user to interrupt any process at any time.

Many command windows may be created in the Console:

Python interpreter
Running Python script
System command window (this terminal emulation window has quite limited features compared to a real terminal: it may be useful on Windows platforms where the system terminal is not much more powerful - on the contrary, on GNU/Linux, a real system terminal is opened, outside Spyder)

Python-based command windows support the following features:

Code completion and calltips
Variable explorer with GUI-based editors for arrays, lists, dictionaries, strings, etc.
Debugging with standard Python debugger (pdb): at each breakpoint the corresponding script is opened in the Editor at the breakpoint line number
User Module Deleter