Question

I have a csv file with 20 fields: v1:v20. Is there any way to add another field after v5 which would be the concatenation of fields 2 to 5? For example, let’s say the file header is:

v1, v2, v3, v4, v5, v5, v7,...
a,  b,  c,  d,  e,  f,  g,....

I want it to look like this:

v1, v2, v3, v4, v5, new.field, v5, v7,...
a,  b,  c,  d,  e,   bcde,     f,  g,...

Answer 1

gawk -F ' *, *' -v OFS=',' '
{
    $6 = (NR==1 ? "new.field," : $2 $3 $4 $5 ",") $6
    print
}' input.csv

---

result:

v1,v2,v3,v4,v5,new.field,v5,v7,...
a,b,c,d,e,bcde,f,g,....