text: import numpy as np
  import pandas as pd
  import time
  
  # ------------------------------------------------------------------------------
  
  print(f"Starting ... {int(time.time())}");
  
  length: int = 1100000000
  
  df = pd.DataFrame({"INDEX": np.arange(0, length),
                     "normal": np.random.normal(size=length),
                     "log_normal": np.random.lognormal(size=length),
                     "exponential": np.random.exponential(size=length),
                     })
  df.set_index("INDEX")
  
  print(f"All memory allocations are done. Calculating means ... {int(time.time())}")
  
  m1: pd.Series = df["normal"].ewm(span=3).mean()
  m2: pd.Series = df["log_normal"].ewm(span=3).mean()
  m3: pd.Series = df["exponential"].ewm(span=3).mean()
  
  print(f"{m1[100000]}, {m2[100000]}, {m3[100000]}")
  print(f"{int(time.time())} ... Done");
  
  # ------------------------------------------------------------------------------
  
  # Local Variables:
  # mode:Python
  # tab-width:4
  # c-basic-offset:4
  # End:
  