javascript_reduce.js

const characters = [
  {
    name: "Luke Skywalker",
    height: 172,
    mass: 77,
    eye_color: "blue",
    gender: "male",
  },
  {
    name: "Darth Vader",
    height: 202,
    mass: 136,
    eye_color: "yellow",
    gender: "male",
  },
  {
    name: "Leia Organa",
    height: 150,
    mass: 49,
    eye_color: "brown",
    gender: "female",
  },
  {
    name: "Anakin Skywalker",
    height: 188,
    mass: 84,
    eye_color: "blue",
    gender: "male",
  },
];

//Map function!
let _allNames = (characters) => {
  return characters.map((character) => character.name);
};

let _allNamesHeight = (characters) => {
  return characters.map((character) => {
    return {
      name: character.name,
      height: character.height,
    };
  });
};

let _allFirstNames = (characters) => {
  return characters.map((character) => {
    let [firstName, lastName] = character.name.split(" ");
    return firstName;
  });
};

let myMapped = _allFirstNames(characters);

//Total Mass
const totalMass = characters.reduce((total, currentCharacter) => {
  return total + currentCharacter.mass;
}, 0);

const totalHeight = characters.reduce((total, currentCharacter) => {
  return total + currentCharacter.height;
}, 0);

const charactresByEyeColor = characters.reduce((total, currentCharacter) => {
  let color = currentCharacter.eye_color;
  if (total[color]) {
    total[color] = total[color] + 1;
  } else {
    total[color] = 1;
  }
  return total;
}, {});

console.log(charactresByEyeColor);