python [Whizzbang Tech Stuff]

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
======Python======
  * [[https://www.python.org/dev/peps/pep-0008/|PEP 8 -- Style Guide for Python Code]]
  * [[https://pep8.org/]]

  * [[Python Modules and Packages]]
  * [[Python Tools]]
  * [[python:Handling Dates]]


======Core Elements & Constructs======
=====Lists=====
<code python>
l = []
 
l.append("alpha")
l.append("beta")
 
for e in l:
  print(e)
</code>

=====Dictionaries=====
<code python>
d = {'alpha': 'plucky', 'beta': 'scrappy'}

print(d['alpha'])
print(d.get('alpha'))

del d['alpha']

# Remove all elements.
d.clear()

d['gamma'] = 'spunky'

# Delete the dictionary itself.
del d
</code>

<code>
   b={}
=> None
   b["alpha"] = 10
=> None
   b
=> {'alpha': 10}
   del b["alpha"]
=> None
   b
=> {}
</code>

======Basic Structures and Constructs======
  * If the %%__name__%% variable is set to %%__main__%% the module is being loaded as a main script and program entry point. Otherwise it's being loaded as a library module.
<code python>
if __name__ == "__main__":
   print("Hello World.")
else:
   pass
</code>

======Conditionals======
<code python>
num = 100

a = ["alpha", "beta", "gamma"]

if "beta" in a:
    pass
  
if num > 10:
    pass
elif num < 10:
    pass
else:
    pass
</code>

======Loops/Iteration======
<code python>
colors = ["red", "green", "blue"]

for c in colors:
    print("%s" % c)
</code>

=====Iterate over keys and values of dictionary====
<code python>
for k, v in dict.items():
    print(v)
</code>

<code python>
for k in dict.keys():
    print(k + "\n")
</code>
<code python>
for v in dict.values():
    print(v + "\n")
</code>

=====Iterate over indicies and values of sequence=====
<code python>
a = ["a", "b", "c"]

for k, v in enumerate(a):

    print("%s, %s\n" % (k,v))
</code>

======Common Elements and Ways======
======Determine if variable is defined======
<WRAP round info>
It might be a code smell/anti-pattern to test whether or not an identifier is defined. That is, testing whether a variable is defined considered harmful.
</WRAP>
=====Method 1======
<code>
x_exists = 'x' in locals() or 'x' in globals()
</code>

=====Method 2======
<code python>
try:
  x
except NameError:
  x_exists = False
else:
  x_exists = True
</code>

=====Method 3=====
<code python>
hasattr(a, 'property')
</code>

=====Method 4=====
<code python>
if args.file is None or len(args.file) == 0:

    pass
</code>

=======Resources/References======
  * [[http://docs.python-guide.org/en/latest/|The Hitchhiker’s Guide to Python]]
  * [[https://realpython.com/|Real Python]], tutorials and other learning resources