def getFrameLevelDisplacements(nodeFound, start, finish):
  """
  Iterates through the entire time-series data for a given
  body part to extract the X,Y,Z coordinate data.

  Args:
      nodeFound (object): joint object for the targeted body part
      start (int): starting frame number
      finish (int): ending frame number

  Returns:
      list: list of lists of X,Y,Z coordiantes. The number of lists must
      equal to number of frames in the BVH
  """
  displacements = []
  for i in range(start, finish):
    X = nodeFound.trtr[i][0][3]
    Y = nodeFound.trtr[i][1][3]
    Z = nodeFound.trtr[i][2][3]
    displacements.append([X, Y, Z])

  return displacements