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Old 07-23-2010, 10:33 AM   #16
colucix
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Quote:
Originally Posted by hsp40oz View Post
this returned 5795 lines which is kind of strange being its a few hundred more than contained in the HQNlist
You sure there aren't duplicate titles in HQNlist?
 
Old 07-23-2010, 10:33 AM   #17
GrapefruiTgirl
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Is it possible that there are duplicates in one or both of the files? How many lines are in each file exactly?

Code:
cat file | wc -l
Plus, for example, let's say a title in file #1 is "The Road", but there is also a title like "The Road Home". The search for the 1st title will also get a false positive when it encounters the second title.
 
Old 07-23-2010, 10:35 AM   #18
GrapefruiTgirl
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@ colucix - a few days ago, myself and a couple others found similar weirdness, and it may have been due to different versions of `grep` but I cannot recall exactly..
 
Old 07-23-2010, 10:35 AM   #19
hsp40oz
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would using a sed command to get rid of all possible unwanted characters and spaces in both files make it easier?
 
Old 07-23-2010, 10:40 AM   #20
hsp40oz
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Quote:
Originally Posted by GrapefruiTgirl View Post
Is it possible that there are duplicates in one or both of the files? How many lines are in each file exactly?

Code:
cat file | wc -l
Plus, for example, let's say a title in file #1 is "The Road", but there is also a title like "The Road Home". The search for the 1st title will also get a false positive when it encounters the second title.
$ cat Backlist | wc -l
855
$ cat HQNlist | wc -l
5345
 
Old 07-23-2010, 10:49 AM   #21
GrapefruiTgirl
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Quote:
Originally Posted by hsp40oz View Post
would using a sed command to get rid of all possible unwanted characters and spaces in both files make it easier?
My opinion? No. It shouldn't be necessary. When a string variable is quoted, all its characters *should* be made integral to the string as a whole.

Characters such as double-quotations might cause problems.. If you want to see if there's a difference, here's a sed which removes spaces, empty lines, single & double quotes, and colons, and places the results into a new file. You could run this on both files, and then try the grep again to see if there's any difference.

Code:
sed "s/ //g;s/'//g;s/://g;s/\"//g;/^$/d" file >> newfile
 
Old 07-23-2010, 10:54 AM   #22
grail
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Have to say that the grep works just fine for me too using dummy data in colucix's post.
Also I like the following format for the while loop as piping in creates another shell which has given me grief in the past:
Code:
#!/bin/bash

while read line
do
	grep "$line" HQNlist
done< Backlist
 
Old 07-23-2010, 10:55 AM   #23
GrapefruiTgirl
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@ grail - that's a good idea that I should try to get into the habit of using, rather than the pipe. Sometimes it works (the pipe), and sometimes not!
 
Old 07-23-2010, 11:15 AM   #24
hsp40oz
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i did not think there were any duplicates, but I just caught one while scrolling down through the HQNlist. What's worse is there are 3 entries of the same title each with a different ISBN number.

smh


I want to strangle my boss.


...and theres another duplicate.

grep wont return multiple lines if there are duplicates?
 
Old 07-23-2010, 11:17 AM   #25
schneidz
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here's my stab at it:
Code:
#sort Backlist | uniq > Backlist.sort; mv Backlist.sort Backlist #thanks sasha
size=`grep -c . Backlist`
i=1
while [ $i -le $size ]
do
 title=`sed -n "$i"p Backlist`
 grep "$title" HQNlist
 # echo `grep "$title" HQNlist` - count: `grep -c "$title" HQNlist` #thanks sasha
 i=`expr $i + 1`
done

Last edited by schneidz; 07-23-2010 at 11:52 AM.
 
Old 07-23-2010, 11:18 AM   #26
ghostdog74
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Quote:
Originally Posted by GrapefruiTgirl View Post
Code:
echo "$(cat Backlist)" | while read line; do
   grep -e "${line}" HQNlist >> results.omfg
done
don't have to create a subshell using a pipe.

Code:
while read -r line
do
  ......
done <Backlist
 
Old 07-23-2010, 11:21 AM   #27
GrapefruiTgirl
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Quote:
Originally Posted by hsp40oz View Post
grep wont return multiple lines if there are duplicates?
Yes, it *will* return the multiple lines -- every line that matches the regex will be returned -- which I thought that was the "problem" i.e. why there appeared to be more lines returned than were actually present in the HQN file.

But, there'd need to be a WHACK of dupes in one or both files, or a WHACK of examples like I gave about "The Road Home", for there to be many more results returned than titles present in the HQN file..
 
Old 07-23-2010, 11:34 AM   #28
schneidz
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^ fyi: i added some comments to my reply #25 to help mitigate duplicates.
 
Old 07-23-2010, 11:38 AM   #29
GrapefruiTgirl
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EgaDs schneidz, I wonder if there is a more horrid color you could have chosen for those comments?
 
Old 07-23-2010, 11:43 AM   #30
hsp40oz
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Quote:
Originally Posted by GrapefruiTgirl View Post
Yes, it *will* return the multiple lines -- every line that matches the regex will be returned -- which I thought that was the "problem" i.e. why there appeared to be more lines returned than were actually present in the HQN file.

But, there'd need to be a WHACK of dupes in one or both files, or a WHACK of examples like I gave about "The Road Home", for there to be many more results returned than titles present in the HQN file..
OIC.

If there is a title "The Road" it will return "The Road" and also "The Road Home"

I'm thinking that I need to figure out a new approach to extracting these numbers. Or just find each manually, I'd probably be half done by now.
 
  


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