text: import pandas as pd
  from matplotlib import pyplot as plt
  import os
  import sys
  import numpy as np
  
  UPDATABLE = True
  
  LOGDIR = os.path.expanduser("~/navrep/logs/V")
  if len(sys.argv) == 2:
      LOGDIR = sys.argv[1]
  
  plt.close('all')
  while True:
      plt.figure("training log")
      plt.clf()
      logs = sorted(os.listdir(LOGDIR))
      legend = []
      lines = []
      for log in logs:
          if not log.endswith(".csv"):
              continue
          path = os.path.join(LOGDIR, log)
          legend.append(log)
          data = pd.read_csv(path)
          x = data["step"].values
  #         x = np.cumsum(data["train_time_taken"].values) / 3600.
          y = data["cost"].values
          line, = plt.plot(x, y, label=log)
          plt.axhline(np.min(y), alpha=0.3, linewidth=1, color=line.get_color())
          lines.append(line)
      plt.legend()   # quick-search : plot tcn training logs
      plt.ion()
      plt.pause(10.)
  