PythonBasics

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Simple Variables

Basic Math

Ints and Floats

Booleans

Deleting Variables

Checking Whether a Variable Exists

Data Collections: Lists

Lists are one of the fundamental data collections in python (we will also discuss dictionaries and you may want to read about tuples and sets).

Data Collections: Dictionaries

Dictionaries are another basic python data collection. Dictionaries store data in pairs, with a set of unique keys each mapped to some value (the values do not have to be unique). Dictionaries are extremely useful in scripting. For example, imagine that we are reducing a complex set of observations and want to be able to look up a the calibrator associated with a given source.

Control Flow

If

While

For

Break/Continue

More Complex Programs

Executing Scripts

The most basic way to execute a set of python commands (aside from just copying and pasting to the shell) is to use the execfile command. Calling execfile('myscript.py') from inside a python shell will execute 'myscript.py' one line at a time. You can use this to run a series of reduction commands or other simple scripts.

A simple example

Functions

Python allows you to define functions either from the command line (or an execfile call) or as part of modules.

Modules

Object Oriented Aspects

Tips and Tricks

Pasting Code

Getting Help, Exploring Objects

Things That Work Only in the Shell