ti-setup-script/utils.js

// Even-probability shuffle
// https://en.m.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
export function shuffle(array) {
  for (let i = array.length - 1; i > 0; i--) {
    let j = Math.floor(Math.random() * (i + 1));
    [array[i], array[j]] = [array[j], array[i]];
  }
  return array;
}


export function checkRemovedCount(oldArray, newArray, removedItems) {
  const expectedLength = oldArray.length - removedItems.length
  return newArray.length === expectedLength
}

export function splitArray(array, numPieces) {
  return array.reduce((splitArrays, item, index) => {
    const position = index % numPieces;
    return [
      ...splitArrays.slice(0, position),
      [...(splitArrays[position] || []), item],
      ...splitArrays.slice(position + 1)
    ];
  }, Array.from({ length: numPieces }, () => []));
}

export function annotateArray(labels, data) {
  return labels.reduce((zipped, label, index) => {
    return {...zipped, [label]: data[index]}
  }, {})
}

export function getRandomItem(array) {
  const index =  Math.floor(Math.random() * array.length)
  return array[index]
}