How do I print the number of lines from a File that contains a specific word using Python?
Question
This prints out the number of all the lines:
def links(htmlfile):
infile = open('twolinks.html', 'r')
content = infile.readlines()
infile.close()
return len(content)
print("# of lines: " + str(content.count('</a>')))
But I only need the number of lines which contain < / a > at the end.
5 answers
solution1
2 2015-10-03 20:45:11
The loop way:
with open('twolinks.html') as f:
count = 0
for line in f:
if line.endswith('</a>'):
count += 1
Using comprehension:
with open('twolinks.html') as f:
sum( 1 for line in f if line.endswith('</a>') )
Or even shorter (summing booleans, treating them as 0s and 1s):
sum( line.endswith('</a>') for line in f )
solution2
1 2015-10-03 21:03:25
import re
with open('data') as f:
print(sum( 1 for line in f if re.search('</a>',line) ))
solution3
1
num_lines = sum(1 for line in open('file') if '</a>' in line)
print num_lines
solution4
0 2015-10-03 21:46:43
I guess that my answer is a bit longer in terms of code lines, but why not use a HTML parser since you know that you are parsing HTML? for instance:
from HTMLParser import HTMLParser
# create a subclass and override the handler methods
class MyHTMLParser(HTMLParser):
def __init__(self):
HTMLParser.__init__(self)
self.count = 0
def handle_endtag(self, tag):
if tag == "a":
self.count += 1
print "Encountered an end tag :", tag
print self.count
# instantiate the parser and fed it some HTML
parser = MyHTMLParser()
parser.feed('<html><head><title>Test</title></head>'
'<body><h1>Parse me!</h1><a></a></body></html>')
this is modified code from the python pages. This is then easier to modify if you find the need for collecting other tags, or data with tags etc.
solution5
-1 2015-10-03 21:22:26
Or you could do something like that:
count = 0
f = open("file.txt", "r")
for line in f:
if(line[-5:].rstrip('\n')=='</a>'):
count+=1
Worked great for me.
In general, you go through the file each line at a time, and see it the last characters (without the \\n ) match </a> . see if the \\n striping gives you any trouble.
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