code: def time_coef(tc, nc, tb, nb):
      
      tc = float(tc)
      nc = float(nc)
      tb = float(tb)
      nb = float(nb)
      q = (tc * nb) / (tb * nc)
      return q
docs: Return time coefficient relative to base numbers.
      @param  tc:     current test time
      @param  nc:     current test data size
      @param  tb:     base test time
      @param  nb:     base test data size
      @return:        time coef.