Sum values from an array of key-value pairs in JavaScript

by

You could use the Array.reduce method:

const myData = [
  ['2013-01-22', 0], ['2013-01-29', 0], ['2013-02-05', 0],
  ['2013-02-12', 0], ['2013-02-19', 0], ['2013-02-26', 0], 
  ['2013-03-05', 0], ['2013-03-12', 0], ['2013-03-19', 0], 
  ['2013-03-26', 0], ['2013-04-02', 21], ['2013-04-09', 2]
];
const sum = myData
  .map( v => v[1] )                                
  .reduce( (sum, current) => sum + current, 0 );
  
console.log(sum);

See MDN

More Related Contents:

  1. adding array elements with for loop JavaScript
  2. Loop through an array in JavaScript
  3. Why is using “for…in” for array iteration a bad idea?
  4. What is the difference between ( for… in ) and ( for… of ) statements?
  5. Remove items from array with splice in for loop [duplicate]
  6. Check if object value exists within a Javascript array of objects and if not add a new object to array
  7. JavaScript Loops: for…in vs for
  8. Why is the loop assigning a reference of the last index element to? [duplicate]
  9. How do I group items in an array by date?
  10. JavaScript – Nuances of myArray.forEach vs for loop
  11. Two arrays, where items in array x can be in array y but not vice versa, test all permutations
  12. push() a two-dimensional array
  13. Javascript: hiding prototype methods in for loop?
  14. Difference between ( for… in ) and ( for… of ) statements?
  15. Sorting array of object based on range of Numbers of String [closed]
  16. How to remove item from array by value? [duplicate]
  17. How to detect if a variable is an array
  18. What is the most efficient way to reverse an array in Javascript?
  19. JavaScript loop variable scope
  20. How can I find matching values in two arrays? [duplicate]
  21. Sort an array with arrays in it by string
  22. Unpacking array into separate variables in JavaScript
  23. How to check identical array in most efficient way? [duplicate]
  24. Using Array objects as key for ES6 Map
  25. Uncaught TypeError: Object.values is not a function JavaScript
  26. Multiple markers Google Map API v3 from array of addresses and avoid OVER_QUERY_LIMIT while geocoding on pageLoad
  27. Normalize Array methods and return values
  28. Why can’t I check if an array is empty with array == []?
  29. javascript – find unique objects in array based on multiple properties
  30. How do I get the last 5 elements, excluding the first element from an array?

Leave a Comment