Replace every second instance of delimeter

Shell Programming and Scripting
1

Hi,

Need help on replacing every second instance of delimeter.

Scenario:

var="Name1,Value1,Name2,Value2,Name3,Value3,Name4,Value"

I want every second "," to replace with "|"

I tried like below

echo $var| sed 's/,/|/2'

But, it's not working.

Expected output:

"Name1,Value1|Name2,Value2|Name3,Value3|Name4,Value"

TIA

2

How about

echo $var| sed 's/,\([^,]*\),/,\1|/g'
Name1,Value1|Name2,Value2|Name3,Value3|Name4,Value
1 Like
3

Hello Sumanthsv,

Following may help you in same.

awk -F, '{for(i=1;i<=NF;i++){OFS=i%2==0?",":"|";Q=Q?Q OFS $i:$i};print Q;Q=""}'  Input_file

Output will be as follows.

var="Name1,Value1|Name2,Value2|Name3,Value3|Name4,Value"

If you doesn't want to read from Input_file then use following command.

echo $var | awk -F, '{for(i=1;i<=NF;i++){OFS=i%2==0?",":"|";Q=Q?Q OFS $i:$i};print Q;Q=""}'

Where variable named var has same value which you have posted into your post.

Thanks,
R. Singh

1 Like
4

Here are two other ways to do what you seem to want; one with sed and one just using shell built-ins. (Note that in this suggested code the string assigned to var starts with a <tab> followed by a <space> and ends with a <space> followed by a <tab> and all of the spaces and tabs are preserved in the output):

#!/bin/ksh
var='	 Name 1,Value 1,"Name 2",Value 2,Name 3 , Value 3 	'
printf '%s\n' "$var"|sed 's/\([^,]*,[^,]*\),/\1|/g'

(	IFS=","
	set -- $var
	while [ $# -gt 2 ]
	do	printf '%s,%s|' "$1" "$2"
		shift 2
	done
	[ $# -eq 0 ] && echo ''
	[ $# -eq 1 ] && printf '%s\n' "$1"
	[ $# -eq 2 ] && printf '%s,%s\n' "$1" "$2"
)

The above script produces the output:

	 Name 1,Value 1|"Name 2",Value 2|Name 3 , Value 3 	
	 Name 1,Value 1|"Name 2",Value 2|Name 3 , Value 3

(unfortunately, the CODE tags seem to be stripping off the trailing <space> and <tab> characters on the last line). So too verify that the spaces and tabs were preserved, when that script's output is piped through od -bc , the output is:

0000000   011 040 116 141 155 145 040 061 054 126 141 154 165 145 040 061
          \t       N   a   m   e       1   ,   V   a   l   u   e       1
0000020   174 042 116 141 155 145 040 062 042 054 126 141 154 165 145 040
           |   "   N   a   m   e       2   "   ,   V   a   l   u   e    
0000040   062 174 116 141 155 145 040 063 040 054 040 126 141 154 165 145
           2   |   N   a   m   e       3       ,       V   a   l   u   e
0000060   040 063 040 011 012 011 040 116 141 155 145 040 061 054 126 141
               3      \t  \n  \t       N   a   m   e       1   ,   V   a
0000100   154 165 145 040 061 174 042 116 141 155 145 040 062 042 054 126
           l   u   e       1   |   "   N   a   m   e       2   "   ,   V
0000120   141 154 165 145 040 062 174 116 141 155 145 040 063 040 054 040
           a   l   u   e       2   |   N   a   m   e       3       ,    
0000140   126 141 154 165 145 040 063 040 011 012                        
           V   a   l   u   e       3      \t  \n                        
0000152

This was tested using a Korn shell, but should work with any POSIX-conforming shell.

Note that using printf '%s\n' "$var" instead of echo $var protects you in cases where the expansion of $var contains any <tab> characters; adjacent <space> characters; and depending on what operating system and shell you're using, any backslash characters ( \ ) that could yield unexpected transformations.

1 Like
5

Thanks a lot...Its working fine.