getPeakHours.js

function getPeakHours(feeds, consideration) {
  const feedCount = feeds.length
  // check if all feeds has a length of 12
  for (let i in feeds) {
    if (feeds[i].length !== 24) {
      return 'rejected: feed must have a length of 24'
    }
  }
  // get hour averages
  let hourAverages = []
  for (let i in [...Array(24).keys()]) {
    i = parseInt(i)
    let iHourSum = 0
    for (let ii in feeds) {
      iHourSum += feeds[ii][i]
    }
    let hourAvg = iHourSum/feedCount
    hourAverages.push(hourAvg)
  }
  // get the highest count
  let highestCount = Math.max(...hourAverages)
  let considerationFromMax = highestCount * consideration
  // collect peak hours
  let peakHours = []
  for (let i in hourAverages) {
    if (hourAverages[i] >= considerationFromMax) {
      peakHours.push({hour: i, count: hourAverages[i]})
    }
  }
  // group peak hours to create peak hour ranges
  let peakHourRanges = []
  let i = 0
  let hourRange = []
  while (i < peakHours.length) {
    if (peakHours.length === 1) {
      peakHourRanges.push([peakHours[i]])
      break
    }
    if (hourRange.length === 0) {
      hourRange.push(peakHours[i])
      i++
      continue
    }
    if (parseInt(hourRange[hourRange.length - 1].hour) + 1 === parseInt(peakHours[i].hour)) {
      hourRange.push(peakHours[i])
      if (i === peakHours.length - 1) {
        peakHourRanges.push(hourRange)
      }
    }
    else {
      peakHourRanges.push(hourRange)
      hourRange = []
    }
    if (hourRange.length === 0) {
      if (hourRange[hourRange.length -1] === peakHours[i]) {
        i++
        continue
      }
      hourRange.push(peakHours[i])
      peakHourRanges.push(hourRange)
    }
    i++
  }
  peakHourRanges = [...new Set(peakHourRanges)]
  function convertToStandard(militaryHour) {
    if (militaryHour > 24 || militaryHour < 0) {
      return false
    }
    let suffix = militaryHour < 12 || militaryHour === 24 ? 'AM' : 'PM'
    let standardTime = militaryHour
    if (militaryHour === 0) {
      standardTime = 12
    }
    if (militaryHour > 12) {
      standardTime = militaryHour % 12
      standardTime = standardTime === 0 ? 12 : standardTime
    }
    return `${standardTime}${suffix}`
  }
  let output = []
  for (let i in peakHourRanges) {
    let x = {}
    if (peakHourRanges[i].length === 1) {
      x.hour = `${convertToStandard(parseInt(peakHourRanges[i][0].hour))} - ` +
      `${convertToStandard(parseInt(peakHourRanges[i][0].hour) + 1)}`
      x.countAvg = peakHourRanges[i][0].count
      output.push(x)
      continue
    }
    x.hour = `${convertToStandard(parseInt(peakHourRanges[i][0].hour))} - ` +
    `${convertToStandard(parseInt(peakHourRanges[i][peakHourRanges[i].length -1].hour) + 1)}`
    x.countAvg = 0
    for (let ii in peakHourRanges[i]) {
      x.countAvg += peakHourRanges[i][ii].count
    }
    output.push(x)
  }
  return output
}

// sample feed
feeds = [
  [0, 45, 22, 45, 60, 65, 78, 22, 0, 11, 34, 40, 2, 45, 21, 62, 40, 55, 32, 65, 69, 54, 4, 60],
  [2, 35, 21, 71, 50, 55, 22, 65, 29, 14, 4, 60, 22, 35, 71, 41, 50, 25, 72, 35, 29, 44, 24, 40]
]

console.log(getPeakHours(feeds, .79))