ESC-HoF.js

Challenge #1
Use .map() or .filter() to complete the following exercises:

Write a function that takes in an array and returns a new array with all numbers multiplied by 10.

Expected output --> [30, 90, 150, 40, 100]

var arr1 = [3, 9, 15, 4, 10]
//Create a function that takes in an array
const newArr = (array) => {
//Create a higher order function map for the array and save it as a variable
//Use map to multiply each value by 10
  let mult10 = array.map(value => value*10)
  //Return all numbers multipled by 10
  return mult10
}
console.log(newArr(arr1));

CHALLENGE 2
// Write a function that takes in an array and returns a new array with only odd numbers. Expected output --> [7, 3, 5, 13]

var arr2 = [2, 7, 3, 5, 8, 10, 13]

//Create a function to accepts an array
const newArray = (array) => {
//Create a variable to hold new filtered array to draw odd numbers using modulo (%2!==0)
  let oddNums = array.filter (value => {
//Utilize the filter method to draw odd numbers
    return value %2 !==0
  })
//Return new filtered array
  return oddNums
}
console.log(newArray(arr2))

// Challenge 3
// Write a function that takes in an array of numbers and letters and returns a string with only the letters. HINT: Use typeof method
var comboArr = [7, "n", "i", "c", 10, "e", false, "w", 3, "o", "r", "k"] 
// Expected output --> "nicework"

// create a function that accepts any array
const findLetters = (array) => {
  // create a variable to hold a new filtered array
  let letters = array.filter(value => {
    // use typeof method using "string" to get the letters in the  new array
    return typeof value === "string"
  })
  // use join to convert the new array into the string and return it
  return letters.join("")
}
//call the function
console.log(findLetters(comboArr));



STRETCH Challenge #1
Create a function that takes in a string and returns a new string with all the vowels removed.
Expected output --> "jvscrpt s wsm"

var str = "javascript is awesome"

//Create a function that takes in a string
const newString = (anyString) => {
//Take the string and turn into an array using .split(", ")
  let stringToArray = anyString.split("")
//Create a variable to hold array and use .filter to get consonants aka not a vowel
  let newArray = stringToArray.filter(value => {
    return value !== "a" && value !== "e" && value !== "i" && value !== "o" && value !== "u"
  }
  )
//Return the new array
//Use join to conver the new array into the string and return it
return newArray.join("")
}

console.log(newString(str))