code: def pvi(
      close, volume, length=None, initial=None, offset=None, **kwargs
  ):
      """Indicator: Positive Volume Index (PVI)"""
      # Validate arguments
      length = int(length) if length and length > 0 else 1
      # min_periods = int(kwargs["min_periods"]) if "min_periods" in kwargs and kwargs["min_periods"] is not None else length
      initial = int(initial) if initial and initial > 0 else 1000
      close = verify_series(close, length)
      volume = verify_series(volume, length)
      offset = get_offset(offset)
  
      if close is None or volume is None:
          return
  
      # Calculate Result
      signed_volume = signed_series(volume, 1)
      pvi = (
          roc(close=close, length=length)
          * signed_volume[signed_volume > 0].abs()
      )
      pvi.fillna(0, inplace=True)
      pvi.iloc[0] = initial
      pvi = pvi.cumsum()
  
      # Offset
      if offset != 0:
          pvi = pvi.shift(offset)
  
      # Handle fills
      if "fillna" in kwargs:
          pvi.fillna(kwargs["fillna"], inplace=True)
      if "fill_method" in kwargs:
          pvi.fillna(method=kwargs["fill_method"], inplace=True)
  
      # Name and Categorize it
      pvi.name = f"PVI_{length}"
      pvi.category = "volume"
  
      return pvi
  
label_desc: Use image node_id 1 for calling a global function with example usage: pvi(close, volume, length, initial, offset) and returns: pvi