Insertion syntax for regex in Notepad++ or Perl - regex

Question

Shortform: searching:
"{,[0-9][0-9]," inserting Space+00... getting replaced string segment:
"{,SPACE00[0-9][0-9]," or other so-garbaged data for found [0-9][0-9] sequence ... so how do I search with a regex and insert in the middle???
Longform question:
I'm trying to do a series of simple character insertions -- digits actually -- in a series of mixed model CSV profiling data (five files each with different model parameters, several hundred lines each).
I'm visually challenged and desire to insert padding characters to columize data, so I can focus on tweaking key values, not keeping place data file to data file.
This need where the CSV data lines format are:
*Variable_symbolic-name*,{##,##,* ... ('Set of CSV Numerical Data lists' ...},\n*
an actual data line:
61,parameter17,{,70,6,1,-1,3, 00,0,0,0,0,},,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
to be morphed to:
61,parameter17,\t\t{, 0070,6,1,-1,3, 00,0,0,0,0,},,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Give or take a tab character to align all the { numeric field starts...
I've found searching: "{,[0-9][0-9]," failed but "\{,[0-9][0-9]," succeeds for the find part of the search and replace operation... but have hit a proverbial brick wall in how to do the actual replace (with an insert) of such a short length. (Obviously with so many parameters and files, I'm moving cautiously!)
However, This Perl Help tutorial leaves me in the dark as to how to keep the found ranges and insert padding before (Space, zero, zero to be specific if positive, '-00' if negative) In short, I need to know how to insert 2-3 places in the replace field in Notepad++... and retain the original data without prejudicing it!
Articles herein have cited replacing paragraphs and lines, adding newlines, etc. but this simple insertion alteration seems too simple for you all. But it's been several hours of frustration for me!
Thanks! // Frank
Resolved:
Good news: ({,)([0-9][0-9],) and \1 xx\2 works fine as does ({,)(#[0-9][0-9],) and replacing with \1 xx#\2 ... whether or not tabs are utilized. Obviously the key was ([0-9][0-9],) which included the discrimination of the comma... though I have no idea why that seemed to fail an hour ago with trials made using Sobrinho's help. Must have not tried the sequence. Thanks all!

Answer 1

Try to type this in the search box:
(.+)(\{,[0-9][0-9].*)
And in the replace:
\1\t\t\2
When you have things between parenthesis, they are "stored" by Notepad++ and can be reused in the replace box.
The order of the parenthesis starts with one and are accessed as \1, \2, ...

Answer 2

You tagged it as Perl, so here is how you do it in Perl ...
I prefer to use lookahead assertions rather than backreferences
s/(?= {,[0-9][0-9], ) /\t\t/x
Alternatively, $& contains the matched string ($0 is something different)
s/ {,[0-9][0-9], /\t\t$&/x

Answer 3

You will need a backreference here, meaning something which, in the replace part, will be equal to what you have matched.
Usually, the whole matched part is stored in the $0 backreference. (You can get $1 with a capture group too, and up to $2 with two capture groups, etc)
Back to your question, you could try this:
Find:
(\{,)([0-9][0-9],)
Replace by:
\t\t$1 00$2
This will insert two tab characters before the part that matched \{,[0-9][0-9], (or in other words, replace the part that matched by 2 tab characters and what you matched), then put the first captured part ({,) and then the space and double 0's and then the second captured part, the two digits and following comma.
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