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python toolbox

Your Python Toolbox

You’ve got Chapter 5 under your
belt and you’ve added some more
CHAPTER 5
Python techiques to your toolbox.

Python Lingo ƒ The sort() method changes the

• “In-place” sorting - transforms ordering of lists in-place.

and then replaces.
The sorted() BIF sorts most any data
• “Copied” sorting - transforms ƒ structure by providing copied sorting.
and then returns. ƒ Pass reverse=True to either
• “Method Chaining” - reading ƒ data in descending order.
sort() or sorted() to arrange your
from left to right, applies a
collection of methods to data.
When you have code like this:
• “Function Chaining” - reading new_l = []
for t in old_l:
from right to left, applies a

new_l.
collection of functions to data.
append(len(t))
rewrite it to use a list comprehension,
like this:
new_l = [len(t) for t
More Python Lingo in old_l]
ƒ To access more than one data item from
• “List Comprehension” - specify
a list, use a slice. For example:
a transformation on one line (as
my_list[3:6]
opposed to using an iteration).
accesses the items from index location 3
up-to-but-not-including index location 6.
• A “slice” - access more than one
item from a list.
ƒ Create a set using the set() factory
function.
• A “set” - a collection of
unordered data items that
contains no duplicates.

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