class_docstr: Rate of change Percentage
  ROC measures the percentage change in price from one period to the next.
  The ROC calculation compares the current price with the price `n`
  periods ago.
  Formula for calculation: ((price - prevPrice) / prevPrice) * 100
  price - the current price
  prevPrice - the price n days ago, equals window length
code: def compute(self, today, assets, out, close):
      today_close = close[-1]
      prev_close = close[0]
      evaluate(
          "((tc - pc) / pc) * 100",
          local_dict={"tc": today_close, "pc": prev_close},
          global_dict={},
          out=out,
      )
  
imports: from __future__ import division
  from numpy import abs, average, clip, diff, dstack, inf
  from numexpr import evaluate
  from zipline.pipeline.data import EquityPricing
  from zipline.pipeline.factors import CustomFactor
  from zipline.pipeline.mixins import SingleInputMixin
  from zipline.utils.input_validation import expect_bounded
  from zipline.utils.math_utils import nanargmax, nanargmin, nanmax, nanmean, nanstd, nanmin
  from zipline.utils.numpy_utils import rolling_window
  from .basic import exponential_weights
  from .basic import LinearWeightedMovingAverage, MaxDrawdown, SimpleMovingAverage, VWAP, WeightedAverageValue
label_desc: Use image node_id 1 for calling the RateOfChangePercentage obj's underlying member method code with example usage: obj.compute(today, assets, out, close) without return types