Rearranging columns using awk

awktext processing

I am trying to move 7th column of my csv file to the end by using

awk -F '{print $1,$2,$3,$4,$5,$6,$8,$9,$10,$11,$7}',OFS= "$file"

where $file is a .csv file in a directory. However, the output is

awk:                          ^ syntax error

Does anyone know how to fix this error?

Best Answer

The -F option needs an argument (field separator): -F, for example.

The end of the awk script must be separated with a (space char) with the rest of the parameters.

If the field separator is , and you wish to keep it, and if the number of column is constant and lower than or equal to 11, give a try to this:

awk -F, '{print $1,$2,$3,$4,$5,$6,$8,$9,$10,$11,$7}' OFS=, "$file"

If your field separator is a semicolon don't forget to set it in quotes like so

awk -f';' '{print $1,$2,$3,$4,$5,$6,$8,$9,$10,$11,$7}' OFS=';' "$file"

Related Solutions

awk Command – Remove Columns with ‘-‘ in First Line

$ cat tst.awk
NR == 1 {
    for (i=1; i<=NF; i++) {
        if ($i != "-") {
            f[++numOutFlds] = i
        }
    }
}
{
    for (i=1; i<=numOutFlds; i++) {
        printf "%s%s", $(f[i]), (i<numOutFlds ? OFS : ORS)
    }
}

$ awk -f tst.awk file
M A A
- G -
M - -

AWK Numerical Sorting – How to Sort Each Column Individually

You can do it in a single GNU awk:

gawk -F ',' '
    {
        for(i=1;i<=NF;i++){matrix[i][NR]=$i}
    }
    END{
        for(i=1;i<=NF;i++){asort(matrix[i])}
        for(j=1;j<=NR;j++){
            for(i=1;i<NF;i++){
                printf "%s,",matrix[i][j]
            }
            print matrix[i][j]
        }
    }
' file

for(i=1;i<=NF;i++){matrix[i][NR]=$i}

Multidimensional array (GNU extension) matrix gets populated, so that matrix[i][j] contains the number of column i, row j.

for(i=1;i<=NF;i++){asort(matrix[i])}

Sorts each column (GNU extension).

Finally

for(j=1;j<=NR;j++){
    for(i=1;i<NF;i++){
        printf "%s,",matrix[i][j]
    }
    print matrix[i][j]
}

Prints a sequence of a[1],, a[2],, ..., a[NF-1],, a[NF]\n for each line.

Best Answer

Related Solutions

awk Command – Remove Columns with ‘-‘ in First Line

AWK Numerical Sorting – How to Sort Each Column Individually

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