Change numbers in a file, incrementing them

Shell Programming and Scripting
1

Hello,

Here's a file of mine:

key1:431
key2:159
key3:998

I need to change these keys to something bigger - and I actually need to shift them all by a range of 3.

The output would be:

key1:434
key2:162
key3:1001

I can't find the propper sed/awk line that would alter all my lines.

The plan-B would be to parse each line, get the value, increment it, and replace it. But I'm sure there's something smarter. .

Thanks

2

Actually there isn't and its almost a one-liner (at least for a file as simple as you have presented it).

I hate to admit it but arithmetics in sed is beyond its capabilities. I already tried that for fun but gave up.

bakunin

3

if all you have is key:val then awk is good at math:

$ printf '%s\n' key1:431 key2:159 key3:998 | awk -F: '{print $1 FS 3+$2}'
key1:434
key2:162
key3:1001
4

My file is a bit tricker than that (most of the lines don't have the key:value thing, and the "key:value" thing is more like "id1-id2-key_value_comment-id3_id3" (- and _ are "separators", but I suppose -F with awk will do what I want)

Example of the file:

name-firstname
number-street-zip_city
phone_email
eggs_value1_discounts-Y/N
tomatoes_value2_discounts-Y/N
bread_value3_discounts-Y/N
wholebread_value4_discounts-Y/N

etc.

We need to increase all the bread things when someone buys some bread.

5

You can use [-_] as field sep. And possibly filter those lines with NF==7 . Let us know if you need more help.