Get all UCSC refseq and calculate first intron length and normalized first intron length

firstIntronLength.awk

BEGIN   {
    FS="\t";
    }

    {
    split($10,exonStarts,",");
    split($11,exonEnds,",");
    geneSize=1.0*int($6)-int($5);
    exonCount=int($9);
    if(exonCount<2)
        {
        next;
        }
    if($4=="+")
        {
        printf("%i\t%f\t%s\n",(exonStarts[2]-exonEnds[1]),(exonStarts[2]-exonEnds[1])/geneSize,$0);
        }
    else 
        {
        printf("%i\t%f\t%s\n",(exonStarts[exonCount]-exonEnds[exonCount-1]),(exonStarts[exonCount]-exonEnds[exonCount-1])/geneSize,$0);
        }
    }