code: def _truncate(f, n):
      
      s = "{}".format(f)
      if "e" in s or "E" in s:
          return "{0:.{1}f}".format(f, n)
      i, p, d = s.partition(".")
      return ".".join([i, (d+"0"*n)[:n]])
docs: Truncates/pads a float `f` to `n` decimal places without rounding
  
      From https://stackoverflow.com/a/783927/1307974 (CC-BY-SA)