Great Python workshop at AAS

Demitri Muno held a great workshop at the 2013 Long Beach AAS, "Astronomers Learning Python" or somesuch.  Here are my notes on the best stuff I learned.

• To make your code not care where python is, start as "env python".
• None is a special null value.  Better than declaring value as -999.
• The string join operator is +.
• Triple quotes are pretty powerful: d = ''' this is a single string with everything included including linefeeds.'''
• Dictionaries behave like hashes in perl.  Lots of useful ways to sort, work with them.
• Since whitespace controls loops in python, you must pick tabs or spaces, and be consistent.  They recommend tabs.
• Both ! and "not" are the not operator, but "not" is more readable, so preferred.
• Here's how to efficiently loop, and keep track of the index in the loop:

a = ['a', 'b', 'c']

for index, item in enumerate(a): 

     print index, item

• String formatting (this is preferred over deprecated %d style):

print "xxx {0}, {1}".format(math.pi, "b") 

• It is harder to code in python using a standard text editor (emacs or vi).  Better to use a dedicated coding editor.  It will help you!  He recommends TextWranger. 

More later!