#gawk script $Revision: 1.3 $ to generate random DNA/RNA string

#ADPC RNAfold does not care if RNA or DNA base sequence

BEGIN { 
  v = "$Revision: 1.3 $";
  if(seed=="")  seed  = 10175103;
  if(total=="") total = 1;
  srand(seed);
  if(N=="") N = 120;
}
END{
  #print "seed="seed,"N=",N;

  for(k=1;k<=total;k++) {
    printf(">rand_dna.awk %s %d %s\n",substr(v,2,length(v)-2),k,strftime());
    for(i=1;i<=N;i++) printf("%s",base(int(rand()*4)));
    printf("\n\n");
  }
}

function base(k) {
  if(k==0) return "A";
  if(k==1) return "C";
  if(k==2) return "G";
  if(k==3) return "T";
  return "N"; #opps
}