Trim the final digits from the arrays

Question

Trim the final digits from the arrays

I have an array that contains various strings:

var arr = ['1234','23C','456','356778', '56']

My goal is to filter out array elements that are less than 3 characters or more than 4 characters. The resulting array should only include elements with 3 or 4 characters, like so:

arr = ['1234', '23C', '456'];  //only 3 and 4 character strings in the array

Additionally, I would like to modify the array further by removing the last digit from any element that has more than 3 characters. The final array should look like this:

arr = ['123', '23C', '456'];

javascript arrays underscore.js

Answer 1

Answer №1

To start with, you can simply utilize the filter function to eliminate numbers that do not consist of 3 digits.

var values = [1234, 234, 456, 356778, 56];
var filteredValues = values.filter(function(number) {
  return number < 1000 && number >= 100;
});

console.log(filteredValues);

Next, for the second part, the map method can be used. Simply convert the number to a string, check if its length is more than 3, take the substring containing the initial three characters of the string, and then convert it back to a number.

var nums = [1234, 123, 4567, 3333];
var updatedNums = nums.map(function(value) {
  value = value.toString().substring(0, 3);
  return parseInt(value);
});

console.log(updatedNums);

Answer 2

To start with, you can simply utilize the filter function to eliminate numbers that do not consist of 3 digits.

var values = [1234, 234, 456, 356778, 56];
var filteredValues = values.filter(function(number) {
  return number < 1000 && number >= 100;
});

console.log(filteredValues);

Next, for the second part, the map method can be used. Simply convert the number to a string, check if its length is more than 3, take the substring containing the initial three characters of the string, and then convert it back to a number.

var nums = [1234, 123, 4567, 3333];
var updatedNums = nums.map(function(value) {
  value = value.toString().substring(0, 3);
  return parseInt(value);
});

console.log(updatedNums);

Answer 3

Answer №2

If all you need are Array.filter and Array.map, as well as converting strings to numbers.

let arr = [1234, 234, 456, 356778, 56];

let newArr = arr.filter((num) => {
  let str = '' + num;
  return str.length === 3 || str.length === 4;
});

Now for the second scenario:

let newArr = arr.map((num) => {
  let str = '' + num;
  
  if (str.length > 3) {
    str = str.substring(0, 3);
  }
  
  return +str;
});

Answer 4

If all you need are Array.filter and Array.map, as well as converting strings to numbers.

let arr = [1234, 234, 456, 356778, 56];

let newArr = arr.filter((num) => {
  let str = '' + num;
  return str.length === 3 || str.length === 4;
});

Now for the second scenario:

let newArr = arr.map((num) => {
  let str = '' + num;
  
  if (str.length > 3) {
    str = str.substring(0, 3);
  }
  
  return +str;
});

Answer 5

Answer №3

function filterArrayByLength(arr,lowLimit,highLimit){
    var filteredArr=[];
    for(i=0;i<arr.length;i++){
         value=arr[i];
         length=value.length;
         if(length>=lowLimit&&length<=highLimit){
          if(length>lowLimit){
          value=value.substring(0,lowLimit);
          }
          filteredArr.push(value);
         }
     }
     return filteredArr;
}

var array = ['1234','234','456','356778','56'];
array=filterArrayByLength(array,3,4);
console.log(array);

Answer 6

function filterArrayByLength(arr,lowLimit,highLimit){
    var filteredArr=[];
    for(i=0;i<arr.length;i++){
         value=arr[i];
         length=value.length;
         if(length>=lowLimit&&length<=highLimit){
          if(length>lowLimit){
          value=value.substring(0,lowLimit);
          }
          filteredArr.push(value);
         }
     }
     return filteredArr;
}

var array = ['1234','234','456','356778','56'];
array=filterArrayByLength(array,3,4);
console.log(array);

Answer 7

Answer №4

If you want to determine whether a number is either 3 or 4 digits long, simply check if the number falls within the range of 100 and 9999

  let filteredNumbers = arr.filter(function(num) {
    // Check if it's a 3 or 4 digit number
    return num >= 100 && num < 10000;
  });

To truncate four-digit numbers to three digits, you can divide each four-digit number by 10 and then round down to the nearest integer

  let truncatedResults = filteredNumbers.map(function(number) {
    return number >= 1000 ? Math.floor(number / 10) : number;
  });

Answer 8

If you want to determine whether a number is either 3 or 4 digits long, simply check if the number falls within the range of 100 and 9999

  let filteredNumbers = arr.filter(function(num) {
    // Check if it's a 3 or 4 digit number
    return num >= 100 && num < 10000;
  });

To truncate four-digit numbers to three digits, you can divide each four-digit number by 10 and then round down to the nearest integer

  let truncatedResults = filteredNumbers.map(function(number) {
    return number >= 1000 ? Math.floor(number / 10) : number;
  });

Answer 9

Answer №5

This method involves converting the given array into a specific string format 1234,23C,456,356778,56, and then using regular expressions to extract the desired elements.

var arr = ['1234','23C','456','356778', '56'];

console.log(String(arr).match(/\b\w{3}(?=\w?\b)/g));

Simplified Explanation:

Identify all substrings that begin with a word boundary (\b, following a comma or at the start of the string), consist of three alphanumeric characters, and potentially have one extra character before the next word boundary (comma or end of string).

It's important to note that this approach can handle string values, as long as they are made up of alphanumeric characters to maintain the integrity of the word break logic (\b).

Answer 10

This method involves converting the given array into a specific string format 1234,23C,456,356778,56, and then using regular expressions to extract the desired elements.

var arr = ['1234','23C','456','356778', '56'];

console.log(String(arr).match(/\b\w{3}(?=\w?\b)/g));

Simplified Explanation:

Identify all substrings that begin with a word boundary (\b, following a comma or at the start of the string), consist of three alphanumeric characters, and potentially have one extra character before the next word boundary (comma or end of string).

It's important to note that this approach can handle string values, as long as they are made up of alphanumeric characters to maintain the integrity of the word break logic (\b).

Answer 11

Answer №6

 const validNumbers = updated_ImportDetails.ImportData.filter((num) => num.length > 2 && num.length < 4);

const uniqueNumbers = validNumbers.map((num) => num.substring(0, 3)).filter((elem, index, self) => index === self.indexOf(elem));

I found this solution to be effective.

Answer 12

 const validNumbers = updated_ImportDetails.ImportData.filter((num) => num.length > 2 && num.length < 4);

const uniqueNumbers = validNumbers.map((num) => num.substring(0, 3)).filter((elem, index, self) => index === self.indexOf(elem));

I found this solution to be effective.

Trim the final digits from the arrays

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

Answer №6

Similar questions

Oops! Make sure to explicitly allow the dependency @types/html2canvas by adding it to the "allowedNonPeerDependencies" option

Reactivating a React hook following the execution of a function or within a function in ReactJS

Featherlight is experiencing issues with running Ajax requests

Guide to integrating react-phone-number-input into material-ui TextField

Executing Javascript dynamically in VueJS: Learn how to run code from a string efficiently

Executing php class method through ajax with jQuery without requiring a php handler file

Utilizing the getJSON Method to Automatically Fill a Dropdown Selection Element

determine the vertical dimension of the horizontal scrollbar

A PHP "for" loop that iterates through an array and prints out all even numbers, along with calculating the sum of all odd numbers

Adding data to a subdocument array with Mongoose's $push method

Leveraging dynamic anchor tags within a Chrome extension

Tips on using Ajax to post in HTML

Employing a for loop to verify the existence of a JSON key

What steps can be taken to ensure that a dropdown menu responds instantly to the JavaScript code provided?

A guide on setting up dual observables in Angular 2

The dynamic change of a required field property does not occur

Issues with jQuery slide operation

Exploring the Benefits of Using Gatsby with Material-UI: The Importance of Creating a Page

Why is the Twitch api map function returning nothing, while the console log is showing output?

Sorting a select element using Javascript/JQuery while taking into consideration the label attribute present in the options