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awk or sed to print the character from the previous line after the regexp match

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# 1  
Old 12-13-2019
awk or sed to print the character from the previous line after the regexp match

Hi All,

I need to print the characters in the previous line just before the regular expression match
Please have a look at the input file as attached
I need to match the regular expression ^ with the character of the previous like and also the pin numbers Attachment 7913
and the output file should be like this as attached
I am writing the script as stated below
sed -n '/^/{x;p;d;}; x' input_file but how to match the Pin number and character before the regular expression in a single line

awk or sed to print the character from the previous line after the regexp match-input_filepng

awk or sed to print the character from the previous line after the regexp match-output_filepng

Last edited by vbe; 12-13-2019 at 04:59 PM..
# 2  
Old 12-13-2019
Hi, could you please post the input and output sample as code segments and not as attachments?

First off: if you want to match a circumflex, you need to escape with a backslash, since it is a special character in regex:

# 3  
Old 12-15-2019
TCL script to match and extract the substring carrying the regex

Thanks but I am not able to put the same content in the text format since the lines are not getting aligned.
Thats why I have attached the attachments

--- Post updated at 08:46 PM ---

Input file

                                       p p p p p
Pin Numbers                             3 2 1 8 9
                                        1 2 3 4 5

pattern     offset                        
scan1        2965                       H L H L H
scan2        2200                       L H H L H 
scan3        1100                       H L L L L 
scan4        1500                       L L H H H 
scan5        2800                       H H L H H
                                          ^     ^

Please have a look at the attachment
# 4  
Old 12-15-2019
Your post headings are somewhat contradictory. If happy with awk and not insist on TCL, try
awk '
NR < 4          {if (NR == 1) ST = index ($0, "p")
                 for (i=ST; i<=NF; i+=2) P[i] = P[i] $i
!NF             {next

/patt/          {print substr ($0, 1, ST-1), "pin-number expected"

                {getline TMP
                 PTR = 0
                 while (IX = index (TMP, "^"))  {print substr ($0, 1, ST-1), P[IX+PTR], substr ($0, IX+PTR, 1)
                                                 PTR = IX
                                                 TMP = substr (TMP, PTR+1)
' FS="" file
pattern     offset                       pin-number expected
scan1        2965                        p13 H
scan2        2200                        p22 H
scan3        1100                        p22 L
scan4        1500                        p13 H
scan5        2800                        p22 H
scan5        2800                        p95 H

This User Gave Thanks to RudiC For This Post:
# 5  
Old 12-16-2019
Thanks a lot Rudic , Let me try it out
# 6  
Old 12-17-2019
Hi Rudic ,

Thanks it worked , I am trying out same script for one more input file

                              r                                     s       
                              e                                     y       
Pin Numbers                   s                                     n       
                              e p p p p p p p p p p p p p p p p p p c       
                              t a a a a a a a a a a a a a a a a a a h       
                              _ 3 3 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 r       
                              n 0 1 0 1 4 5 6 7 8 9 8 9 2 3 4 5 6 7 o       

pattern         offset   
scan0_core_p    2965          1 1 1 0 1 1 0 1 0 1 0 L L L L L H L L 0       
scan0_core_p    2967          1 1 1 1 1 0 1 0 1 1 1 H H L L L H L L 0       
scan0_core_p    2968          1 1 1 1 0 1 1 0 0 1 1 H L L L H H H L 0       
scan0_core_p    2976          1 1 1 1 0 1 1 1 1 0 0 L L H L L H H L 0       
scan0_core_p    2977          1 1 1 1 1 0 1 1 1 1 0 L H H L L H L L 0       
scan0_core_p    2978          1 1 1 0 0 0 1 0 1 1 0 H H L L L H L L 0       

I am changing the script so that it can work for the above stated input file
I am changing some condition in for loop , Any suggestions ?
# 7  
Old 12-17-2019
What did you try? What did you change? Where and how did it fail?

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