awk to include name in field between location and average -

in awk below location $1 , calculated average $4 printed. can not seem syntax correct include $2 in output between $1 , $4. thank :).

awk '{   if(len==0){      last=$1;total=$4;len=1;getline   }   if($1!=last){       printf("%s\t%f\n", last, total/len);       last=$1;total=$4;len=1   }   else{        total+=$4;len+=1   } } end{   printf("%s\t%f\n", last, total/len) }' input.bed > output.txt 

input.bed

chr1:955542-955763  agrn:exon.1 1   0 chr1:955542-955763  agrn:exon.1 2   0 chr1:955542-955763  agrn:exon.2 3   0 chr1:955542-955763  agrn:exon.2 4   1 

current output.txt

chr1:955542-955763  21.289593 chr1:957570-957852  304.861702 

desired output.txt

chr1:955542-955763 agrn:exon.1  21.289593 chr1:957570-957852 agrn:exon.2  304.861702 

maybe

awk '{if(len==0){last=$1;**name=$2**,total=$4;len=1;getline}if($1!=last){printf("%s\t%f\n", last, ,**name**, total/len);last=$1;name=$2;total=$4;len=1}else{total+=$4;len+=1}}end{printf("%s\t%f\n", last,**name**, total/len)}' input.bed > output.txt 

the input , outputs posted not real #'s don't mean :)

edit:

awk '{for (i=1; i<=nf; i++) print i, $i}' ionxpress_008_150902_4column.bed | head -4 1 chr1:955542-955763 2 agrn:exon.1 3 1 4 0 

i think key should combination of first 2 fields. sample input provided

$ awk '{k=$1 ofs $2; s[k]+=$4; c[k]++} end{for(i in s) print i, s[i]/c[i]}' file 

will produce this

chr1:955542-955763 agrn:exon.1 0 chr1:955542-955763 agrn:exon.2 0.5 

if field 2 not part of key , want have value last row each field 1

$ awk '{k=$1; s[k]+=$4; f2[k]=$2; c[k]++} end{for(i in s) print i, f2[i], s[i]/c[i]}' file 

will produce

chr1:955542-955763 agrn:exon.2 0.25