Find and count matching lines in file

Input and Output in Ruby example from a Well House Consultants training course
More on Input and Output in Ruby [link]

This example is described in the following article(s):
• New to programming? It is natural (but needless) for you to be nervous - [link]

Source code: amaze1 Module: R106

# Sample Ruby program - counting lines and lines matched
# from a log file

print "What do you want to look for? "
interest = STDIN.gets.chop

print "You are looking for ",interest," in the log file\n"

# Open the file - get a file handle
fyle = File.new "ac_20150102"

counter = 0
all = 0
loop do
        lyne = fyle.gets
        # Check if we are at end of file
        break if lyne.nil?
        all = all + 1
        if lyne.include?(interest)
                print lyne
                counter = counter + 1
        end
end
print "We tested ",all," lines\n"
print "We matched ",counter," lines\n"

lines_per_minute = all.to_f / 24.0 / 60.0
print "Busyness was ",lines_per_minute," lines per minute\n"

__END__

Test 1 - Sample

WomanWithCat:r106 grahamellis$ ruby amaze1
What do you want to look for? Trowbridge
You are looking for Trowbridge in the log file
amaze1:11:in `initialize': No such file or directory - ac_20150102 (Errno::ENOENT)
        from amaze1:11:in `new'
        from amaze1:11:in `<main>'
You have new mail in /var/mail/grahamellis
WomanWithCat:r106 grahamellis$

Test 2 - Sample

WomanWithCat:r106 grahamellis$ ruby amaze1
What do you want to look for? Dawlish
You are looking for Dawlish in the log file
62.210.122.209 - - [01/Jan/2015:04:29:03 +0000] "GET /info/11409_Dawlish_sea_wall_webcam.html HTTP/1.1" 200 85534 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
66.249.78.151 - - [01/Jan/2015:05:24:11 +0000] "GET /info/9337_Stock_for_the_Dawlish_Airshow_Thurs_18_August_2011.html HTTP/1.1" 200 10737 "-" "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)"
157.56.1.44 - - [01/Jan/2015:19:44:55 +0000] "GET /info/11409_Dawlish_sea_wall_webcam.html HTTP/1.1" 200 10579 "-" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:44:56 +0000] "GET /coffeeshop/Themes/default/script.js?fin11 HTTP/1.1" 200 13506 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:44:57 +0000] "GET /coffeeshop/Themes/default/style.css?fin11 HTTP/1.1" 200 8739 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:44:57 +0000] "GET /coffeeshop/Themes/default/print.css?fin11 HTTP/1.1" 200 60 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:44:57 +0000] "GET /coffeeshop/Themes/default/sha1.js HTTP/1.1" 200 12815 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:44:57 +0000] "GET /coffeeshop/index.php?PHPSESSID=asjuvvfrfuqbp6pq7r1e4ov1s2&action=dlattach;attach=2329;type=avatar HTTP/1.1" 200 42888 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
msnbot-157-56-1-44.search.msn.com - - [01/Jan/2015:19:44:57 +0000] "GET /qr/img.php?sz=3&server=www.firstgreatwestern.info&page=/coffeeshop/index.php&get=topic=11409 HTTP/1.1" 200 421 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:45:09 +0000] "GET /coffeeshop/Themes/default/xml_topic.js HTTP/1.1" 200 7030 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:45:09 +0000] "GET /coffeeshop/index.php?PHPSESSID=asjuvvfrfuqbp6pq7r1e4ov1s2&action=dlattach;attach=2086;type=avatar HTTP/1.1" 200 42482 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.56.1.44 - - [01/Jan/2015:19:45:09 +0000] "GET /coffeeshop/index.php?PHPSESSID=asjuvvfrfuqbp6pq7r1e4ov1s2&action=dlattach;attach=1536;type=avatar HTTP/1.1" 200 49117 "http://www.firstgreatwestern.info/info/11409_Dawlish_sea_wall_webcam.html" "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0; Trident/5.0)"
157.55.39.232 - - [01/Jan/2015:23:13:49 +0000] "GET /info/7966_MINISTERS_urged_to_continue_investment_in_the_Dawlish_sea_wall_route.html HTTP/1.1" 200 4257 "-" "Mozilla/5.0 (compatible; bingbot/2.0; +http://www.bing.com/bingbot.htm)"
We tested 192645 lines
We matched 13 lines
Busyness was 133.78125 lines per minute
WomanWithCat:r106 grahamellis$

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in Ruby
* Ruby Programming
Also available on on site courses for larger groups

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