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Ubuntu – Copying the fields of one record into the fields of another record in a second file with awk

GNU Awk 5.1.0. zsh, Ubuntu 22.04
I have a source file containing one line records (FS="|") source_file.txt

19-03-2024
Name            | formula           | no.  | dose | days | cost  | msg | em | notes | consult | WYLQ
John Doe        | XJZT+ML+SD        | 9979 | 4¾   | 14   | xx.xx | x   | 2  | xx    | ph      |
Jane Doe        | XJZT-BS+CS+MDP+FL | 9980 | 5    | 10   | xx.xx | x   | 1  | xx    | ph      |

I want to place fields 2,3,4,5 from the selected record from source_file.txt in fields 1,2,3,4 of record 3 of table.txt.

I have used the chain of commands in the terminal as follows:

awk -v FS='|' -v OFS='|' ' $1 ~ /John Doe/ { print $2,$3,$4,$5 }' ~/source_file.txt > /tmp/record_grab.tmp | awk '{a[FNR]=$0}' /tmp/record_grab.tmp | awk -v FS='|' -v OFS='|' 'FNR==NR{a[FNR]=$0; next} {print $1,$2,$3,$4 a[FNR], $3}' /tmp/record_grab.tmp /home/table.txt

The result was:

| formula               | no. | dose      XJZT+ML+SD          | 9979 | 4¾    | 14    | no. 
| --------------------- | --- | -------- | --- 
|                       |     |

The intended result is:

| formula               | no.  | dose     | days    |
| --------------------- | ---  | -------- | ------- |
| XJZT+ML+SD            | 9979 | 4¾       | 14      |

placing fields 2,3,4,5 from the selected record from source_file.txt in fields 1,2,3,4 of record 3 of table.txt

The file record_grab.tmp turned out as intended:

cat /tmp/record_grab
XJZT+ML+SD        | 9997 | 4¾    | 7

I realise there is definitely a more elegant way to do this, that aside I have made a mistake in my use of arrays it looks like it’s put the entire line from the temp file into field 3 of table.txt rather than record 3 somehow and I can’t work out how to correct it. Any help is appreciated.

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2

Answers


  1. 0

    I would harness GNU AWK for this task following way, let file.txt content be

    19-03-2024
Name            | formula           | no.  | dose | days | cost  | msg | em | notes | consult | WYLQ
John Doe        | XJZT+ML+SD        | 9979 | 4¾   | 14   | xx.xx | x   | 2  | xx    | ph      |
Jane Doe        | XJZT-BS+CS+MDP+FL | 9980 | 5    | 10   | xx.xx | x   | 1  | xx    | ph      |

    then

    awk 'BEGIN{FS=OFS="|"}NR==2{print "|" $2,$3,$4,$5 "|";for(i=2;i<=5;i+=1){$i=sprintf("%*s",length($i),"");gsub(/ /,"-",$i)};print "|" $2,$3,$4,$5 "|"}NR>2&&$1~/John Doe/{print "|" $2,$3,$4,$5 "|"}' file.txt

    gives output

    | formula           | no.  | dose | days |
|-------------------|------|------|------|
| XJZT+ML+SD        | 9979 | 4¾   | 14   |

    Explanation: I inform GNU AWK that pipe is both field separator (FS) and output field separator (OFS), for 2nd line I print desired columns encased in |. Then for each selected column I use dynamic sprintf to get string consisting of as many spaces as there characters in given column, which I then globally substitute using dashes. I print it in some manner as headers line. For each line after 2nd line and having John Doe inside 1st field I print desired column encased in |.

    (tested in GNU Awk 5.1.0)

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  2. 0

    This, using any awk, is an untested guess (since no example of table.txt in the question) at what you might be trying to do:

    awk '
    BEGIN { FS=OFS="|" }
    NR == FNR {
        if ( $1 ~ /John Doe/ ) {
            split($0,a)
            nextfile
        }
        next
    }
    FNR == 3 {
        for ( i=1; i<=4; i++ ) {
            $i = a[i+1]
        }
    }
    { print }
' source_file.txt table.txt

    If your awk supports the non-POSIX extension nextfile the above will execute faster than if it doesn’t, but it’ll work either way.

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