Sort rows in csv file without header & first column - awk

Question

I've a CSV file containing records like below.
id,h1,h2,h3,h4,h5,h6,h7
101,zebra,1,papa,4,dog,3,apple
102,2,yahoo,5,kangaroo,7,ape
I want to sort rows into this file without header and first column. My output should like this.
id,h1,h2,h3,h4,h5,h6,h7
101,1,3,4,apple,dog,papa,zebra
102,2,5,7,ape,kangaroo,yahoo
I tried below AWK but don't know how to exclude header and first column.
awk -F"," ' {
s=""
for(i=1; i<=NF; i++) { a[i]=$i; }
for(i=1; i<=NF; i++)
{
for(j = i+1; j<=NF; j++)
{
if (a[i] >= a[j])
{
temp = a[j];
a[j] = a[i];
a[i] = temp;
}
}
}
for(i=1; i<=NF; i++){ s = s","a[i]; }
print s
}
' file
Thanks

Answer 1

If perl is okay:
$ perl -F, -lane 'print join ",", $.==1 ? #F : ($F[0], sort #F[1..$#F])' ip.txt
id,h1,h2,h3,h4,h5,h6,h7
101,1,3,4,apple,dog,papa,zebra
102,2,5,7,ape,kangaroo,yahoo
-F, to indicate , as input field separator, results saved in #F array
See https://perldoc.perl.org/perlrun#Command-Switches for details on other options
join "," to use , as output field separator
$.==1 ? #F for first line, print as is
($F[0], sort #F[1..$#F]) for other lines, get first field and sorted output of other fields
.. is range operator, $#F will give index of last field
you can also use (shift #F, sort #F) instead of ($F[0], sort #F[1..$#F])
For given header, sorting first line would work too, so this can simplify logic required
$ # can also use: perl -F, -lane 'print join ",", shift #F, sort #F'
$ perl -F, -lane 'print join ",", $F[0], sort #F[1..$#F]' ip.txt
id,h1,h2,h3,h4,h5,h6,h7
101,1,3,4,apple,dog,papa,zebra
102,2,5,7,ape,kangaroo,yahoo
$ # can also use: ruby -F, -lane 'print [$F.shift, $F.sort] * ","'
$ ruby -F, -lane 'print [$F[0], $F.drop(1).sort] * ","' ip.txt
id,h1,h2,h3,h4,h5,h6,h7
101,1,3,4,apple,dog,papa,zebra
102,2,5,7,ape,kangaroo,yahoo

Answer 2

if you have gawk use asort:
awk -v OFS="," 'NR>1{split($0, a, ",");
$1=a[1];
delete a[1];
n = asort(a, b);
for (i = 1; i <= n; i++){ $(i+1)=b[i]}};
1' file.csv
This splits the columns to array a with seperator as , for all raws except the first one.
Then assign the first value in the column in a raw with the first value in a and delete this value from a.
Now the a is sorted to b and assign value starting from 2 column. then print it.

Answer 3

You can just use the asort() function in awk for your requirement and start sorting them from second line on-wards. The solution is GNU awk specific because of length(array) function
awk 'NR==1{ print; next }
NR>1 { finalStr=""
arrayLength=""
delete b
split( $0, a, "," )
for( i = 2; i <= length(a); i++ )
b[arrayLength++] = a[i]
asort( b )
for( i = 1; i <= arrayLength ; i++ )
finalStr = (finalStr)?(finalStr","b[i]):(b[i])
printf( "%s", a[1]","finalStr )
printf( "\n" );
}' file
The idea is first we split the entire line with a , delimiter into the array a from which we get the elements from the 2nd field onwards to a new array b. We sort those elements in this new array and append the first column element when we print it finally.