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comprehending data

Comprehending lists

Consider what you need to do when you transform one list into another. Four
things have to happen. You need to:

1 Create a new list to hold the transformed data.

2 Iterate each data item in the original list.

3 With each iteration, perform the transformation.

4 Append the transformed data to the new list.

1. Create.
clean_mikey = [] 2. Iterate.

for each_t in mikey: 3. Transform.
clean_mikey.append(sanitize(each_t))

4. Append.

You get to pick the target
Here’s the same functionality as a list comprehension, which involves
creating a new list by specifying the transformation that is to be applied to each identifier to use (just like with
regular iterations).
of the data items within an existing list.

clean_mikey = [sanitize(each_t) for each_t in mikey]

The new list is created… …by applying a …to each …within an existing list.
transformation… data item…

What’s interesting is that the transformation has been reduced to a single line
of code. Additionally, there’s no need to specify the use of the append()
method as this action is implied within the list comprehension. Neat, eh?

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