Determine the count of distinct elements within an array using Angular 7

Question

Determine the count of distinct elements within an array using Angular 7

Suppose I have an array containing the following objects:

arr = [{name: 'foo', number: 1}, {name: 'foo', number: 1}, {name: 'bar', number: 1}]

How can I determine the count of foo in this array without explicitly passing the name?

search(name, arr) {
    let fooCount = 0;
    let barCount = 0;
    for (let i = 0; i < arr.length; i++) {
      if (arr[i].name === 'foo') {
        fooCount++;
      } else if (arr[i].name === 'bar') {
        barCount++;
      }
    }
    return { foo: fooCount, bar: barCount };
}

This enables me to call the search() function and obtain counts for both foo and bar from the array.

angular typescript

Answer 1

Answer №1

let itemsArray = [{
  name: 'apple',
  quantity: 5
}, {
  name: 'banana',
  quantity: 2
}, {
  name: 'orange',
  quantity: 3
}]

function calculateTotal(input) {
  var totalQuantity = {};

  itemsArray.forEach(item => {
    if (totalQuantity[item.name]) {
      totalQuantity[item.name] += item.quantity;
    } else {
      totalQuantity[item.name] = item.quantity;
    }
  });

  return totalQuantity;
}

var finalResult = calculateTotal(itemsArray);
console.log(finalResult);

You can loop through the items and sum up the quantities for each name that matches. I hope this meets your requirements, but feel free to reach out if you need more clarification.

Answer 2

let itemsArray = [{
  name: 'apple',
  quantity: 5
}, {
  name: 'banana',
  quantity: 2
}, {
  name: 'orange',
  quantity: 3
}]

function calculateTotal(input) {
  var totalQuantity = {};

  itemsArray.forEach(item => {
    if (totalQuantity[item.name]) {
      totalQuantity[item.name] += item.quantity;
    } else {
      totalQuantity[item.name] = item.quantity;
    }
  });

  return totalQuantity;
}

var finalResult = calculateTotal(itemsArray);
console.log(finalResult);

You can loop through the items and sum up the quantities for each name that matches. I hope this meets your requirements, but feel free to reach out if you need more clarification.

Answer 3

Answer №2

Utilize the filter method to achieve this

let items = [{name: 'foo', number: 1}, {name: 'foo', number: 1}, {name: 'bar', number: 1}]

let total = items.filter(item => item.name === "foo").length;
console.log(total)

Answer 4

Utilize the filter method to achieve this

let items = [{name: 'foo', number: 1}, {name: 'foo', number: 1}, {name: 'bar', number: 1}]

let total = items.filter(item => item.name === "foo").length;
console.log(total)

Determine the count of distinct elements within an array using Angular 7

Answer №1

Answer №2

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