Array Cardio Day 1

// Array.prototype.filter()
// 1. Filter the list of inventors for those who were born in the 1500's
const fifteen = inventors.filter(inventor => {
  if(inventor.year >= 1500 && inventor.year < 1600){
    return true
  }
})

// Array.prototype.map()
// 2. Give us an array of the inventors' first and last names
inventors.map(inventor => {
  return inventor.first + " " + inventor.last
})

 // Array.prototype.sort()
 // 3. Sort the inventors by birthdate, oldest to youngest
 inventors.sort((a, b) => a.year > b.year ? 1 : -1)

 // 5. Sort the inventors by years lived
const inventorVitality = inventors.sort((a, b) => {
    lastGuy = a.passed - a.year
    nextGuy = b.passed - b.year
    return lastGuy > nextGuy ? 1 : -1
  })


// 6. create a list of Boulevards in Paris that contain 'de' anywhere in the name
const category = document.querySelector('.mw-category')
const links = [...(category.querySelectorAll('a'))]

const de = links
            .map(link => link.textContent)
            .filter(srteetName => srteetName.includes('de'))

// 7. sort Exercise
// Sort the people alphabetically by last name
const sortingPeople = people.sort((lastOne, nextOne) => {
      const [aLast, aFirst] = lastOne.split(", ");
      const [bLast, bFirst] = nextOne.split(", ");
      return aLast > bLast ? 1 : -1
    })

// 8. Reduce Exercise
// Sum up the instances of each of these
const transporting = data.reduce((obj, item) => {
    if (!obj[item]) {
      obj[item] = 0;
    }
    obj[item]++;
    return obj;
  }, {});


Array Cardio Day 2

// Array.prototype.some() // is at least one person 19 or older
people.some(person => {
  var currentYear = (new Date()).getFullYear();
  return currentYear - person.year
})

// Array.prototype.every() // is everyone 19 or older?
people.every(person => {
  ( (new Date()).getFullYear() ) - person.year >= 19
})

// Array.prototype.find()
// Find is like filter, but instead returns just the one you are looking for
// find the comment with the ID of 823423
comments.find(comment => comment.id === 823423 )

// Array.prototype.findIndex()
// Find the comment with this ID
const index = comments.findIndex(comment => comment.id === 823423)