using a generator to source data from a file
File Handling example from a Well House Consultants training course
More on File Handling [link]
Source code: j2 Module: Y110
""" If you have a huge flow of data to filter for the information you
need in a python program, without reading the entire flow into a list,
you can use xreadlines or readline (but do not use readlines!).
In this example, we use a genarator function called "myset" to return
(yield) one reference in a log file at a time to robots.txt, and we then
process each of those references in our main code. Use of a generator
function line this allows us to iterate through relevant records, and to
do so within a function rather than cluttering up the main code with both
the data sourcing and the data processing, which would lead to the code
being harder to maintain at a later date if the data processing needed to
be updated but the sourcing was unaltered, or if it was going to be split
into separate modules """
fh = open("ac_20101128","r")
notme = 0
lyne = fh.readline()
if not lyne: break
if lyne.find("GET /robots.txt") > -1:
notme += 1
yield "*Summary: " + str(notme)
for number in myset():
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* Learning to program in Python
* Python Programming
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