code: def computeNoCall(fileName):
      
      outputFile = None
      try:
          outputFile = open(fileName + ".noCall", "w")
      except IOError:
          msg = "%s: can't write file" % fileName + ".noCall"
          raise ProgramError(msg)
      print >>outputFile, "\t".join(["PED", "ID", "SEX", "nbGeno", "nbNoCall"])
  
      try:
          toPrint = []
          with open(fileName, "r") as inputFile:
              for i, line in enumerate(inputFile):
                  row = line.rstrip("\r\n").split(" ")
                  if i != 0:
                      # This is data
                      genotypes = np.array(row[6:])
  
                      nbMarker = len(genotypes)
                      nbNA = len(np.where(genotypes == "NA")[0])
  
                      toPrint.append((row[0], row[1], row[4], str(nbMarker),
                                      str(nbNA)))
  
          toPrint.sort(reverse=True, key=lambda values: int(values[4]))
  
          for row in toPrint:
              print >>outputFile, "\t".join(row)
  
      except IOError:
          msg = "%(fileName)s: no such file" % locals()
          raise ProgramError(msg)
  
      # Closing the output file
      outputFile.close()
docs: Computes the number of no call.
  
      :param fileName: the name of the file
  
      :type fileName: str
  
      Reads the ``ped`` file created by Plink using the ``recodeA`` options (see
      :py:func:`createPedChr24UsingPlink`) and computes the number and percentage
      of no calls on the chromosome ``24``.