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PERL : Use of a variable in a tr

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# 1  
Old 01-27-2011
PERL : Use of a variable in a tr
Hi,

I want to count the number of occurences of a character in a string variable ($str). The character is stored in a another variable ($sepchr). I am using tr as :

Code:
 
$count = ($str =~ tr/$sepchr//);

This did not work. I found in another thread about using eval. I used eval as :

Code:
 
$count = ($str =~ eval "tr/$sepchr//");

But this too did not work.

Please advise.

Thanks
sinpeak
# 2  
Old 01-27-2011
I would use global matching for that:

Code:
# perl -le'
  $s = "ababbaa";
  $c = shift;
  $n = () = $s =~ /$c/g;
  print $n;
  ' a
4
# perl -le'
  $s = "ababbaa";
  $c = shift;
  $n = () = $s =~ /$c/g;
  print $n;
  ' b
3

# 3  
Old 02-22-2011
wat does 015 mean in this command?

Code:
tr -d \\015 < file

Last edited by radoulov; 02-22-2011 at 09:45 AM.. Reason: Code tags!
# 4  
Old 02-22-2011
Code:
$ man ascii | grep 015
Reformatting page.  Please Wait... done
     010 BS   011 HT   012 NL   013 VT   014 NP   015 CR   016 SO   117 SI

CR - Carriage Return.
This User Gave Thanks to radoulov For This Post:
xerox
# 5  
Old 02-22-2011
You could use the s/// operator as well, at the expense of modifying the original string -

Code:
$
$
$ perl -le '$str="ababbaa"; $sepchr="a"; $count = $str =~ s/$sepchr//g; print $count'
4
$
$
$ perl -le '$str="ababbaa"; $sepchr="b"; $count = $str =~ s/$sepchr//g; print $count'
3
$
$

tyler_durden
This User Gave Thanks to durden_tyler For This Post:
xerox
# 6  
Old 02-23-2011
many thanks for the previous post....

i want to remove ^M(ctrl-v ctrl-m) from a file through script using sed command...can u suggest sumthin.....

---------- Post updated at 09:33 AM ---------- Previous update was at 09:32 AM ----------

many thanks for the previous post....

i want to remove ^M(ctrl-v ctrl-m) from a file through script using sed command in shell script...can u suggest sumthin.....
# 7  
Old 02-23-2011
Code:
sed 's/^M//g' yourfile > newfile

Last edited by tene; 02-23-2011 at 01:48 AM..
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