code: def main():
      
      N,kappa,D,I=100,20.,0.,90.
      if len(sys.argv)!=0 and  '-h' in sys.argv:
          print(main.__doc__)
          sys.exit()
      elif '-i' in sys.argv:
          ans=input('    Kappa: ')
          kappa=float(ans)
          ans=input('    N: ')
          N=int(ans)
          ans=input('    Mean Dec: ')
          D=float(ans)
          ans=input('    Mean Inc: ')
          I=float(ans)
      else:
          if '-k' in sys.argv:
              ind=sys.argv.index('-k')
              kappa=float(sys.argv[ind+1])
          if '-n' in sys.argv:
              ind=sys.argv.index('-n')
              N=int(sys.argv[ind+1])
          if '-D' in sys.argv:
              ind=sys.argv.index('-D')
              D=float(sys.argv[ind+1])
          if '-I' in sys.argv:
              ind=sys.argv.index('-I')
              I=float(sys.argv[ind+1])
      for k in range(N): 
          dec,inc= pmag.fshdev(kappa)  # send kappa to fshdev
          drot,irot=pmag.dodirot(dec,inc,D,I)   
          print('%7.1f %7.1f ' % (drot,irot))
docs: NAME
          fishrot.py
  
      DESCRIPTION
          generates set of Fisher distributed data from specified distribution 
  
      SYNTAX
          fishrot.py [-h][-i][command line options]
  
      OPTIONS
          -h prints help message and quits
          -i for interactive  entry
          -k kappa specify kappa, default is 20
          -n N specify N, default is 100
          -D D specify mean Dec, default is 0
          -I I specify mean Inc, default is 90
          where:
              kappa:  fisher distribution concentration parameter
              N:  number of directions desired
      OUTPUT
          dec,  inc