I came across with a weird requirement and I am struggling for last few hours to plete it. Below is my Array of string(just an example, the actual array contains around 2500 records):

var testArray = [
  "130,839.9,855,837.3,848.65,3980489", 
  "129,875,875,828.1,833.25,6926078", 
  "138,891.3,893.3,865.2,868.75,5035618"
]

We have 3 element here of which each element is ma separated(each element have 6 item). i.e:

testArray[0] = "130,839.9,855,837.3,848.65,3980489"

My problem is, I wanted to sort testArray based on the first item of each element and convert it to array of array having all value into float, so the output would be:

[
  [129, 875, 875, 828.1, 833.25, 6926078],
  [130, 839.9, 855, 837.3, 848.65, 3980489],
  [138, 891.3, 893.3, 865.2, 868.75, 5035618]
]

I am able to sort individual item but not the entire array as a whole, and I have tried using split and then sort with no luck.

Can someone help me out with this and please let me know if I am not clear.

I came across with a weird requirement and I am struggling for last few hours to plete it. Below is my Array of string(just an example, the actual array contains around 2500 records):

var testArray = [
  "130,839.9,855,837.3,848.65,3980489", 
  "129,875,875,828.1,833.25,6926078", 
  "138,891.3,893.3,865.2,868.75,5035618"
]

We have 3 element here of which each element is ma separated(each element have 6 item). i.e:

testArray[0] = "130,839.9,855,837.3,848.65,3980489"

My problem is, I wanted to sort testArray based on the first item of each element and convert it to array of array having all value into float, so the output would be:

[
  [129, 875, 875, 828.1, 833.25, 6926078],
  [130, 839.9, 855, 837.3, 848.65, 3980489],
  [138, 891.3, 893.3, 865.2, 868.75, 5035618]
]

I am able to sort individual item but not the entire array as a whole, and I have tried using split and then sort with no luck.

Can someone help me out with this and please let me know if I am not clear.

• javascript
• arrays
• sorting
• split
• array-map

• It's always better to show the attempts aswell. – ASDFGerte Commented Jul 14, 2018 at 15:18

4 Answers 4

Convert the array using Array#map within an Array#map, then use Array#sort on the converted array according to the [0] indices (a[0] - b[0]):

In ES5

var testArray = [
  "130,839.9,855,837.3,848.65,3980489", 
  "129,875,875,828.1,833.25,6926078", 
  "138,891.3,893.3,865.2,868.75,5035618"
]

var converted = testArray.map(function (item) {
  return item.split(',').map(function (num) {
    return parseFloat(num);
  });
})
console.log(converted)

var sorted = converted.sort(function (a, b) { return a[0] - b[0] })
console.log(sorted)

In ES6

const testArray = [
  "130,839.9,855,837.3,848.65,3980489", 
  "129,875,875,828.1,833.25,6926078", 
  "138,891.3,893.3,865.2,868.75,5035618"
]

const converted = testArray.map(
  item => item.split(',').map(
    num => parseFloat(num)
  )
)
console.log(converted)

const sorted = converted.sort((a, b) => a[0] - b[0])
console.log(sorted)

In ES6 (condensed)

const testArray = [
  "130,839.9,855,837.3,848.65,3980489", 
  "129,875,875,828.1,833.25,6926078", 
  "138,891.3,893.3,865.2,868.75,5035618"
]

const convertedAndSorted = testArray
  .map(n => n.split(',')
  .map(num => parseFloat(num)))
  .sort((a, b) => a[0] - b[0])

console.log(convertedAndSorted)

Just map the splitted and to number formatted values and sort by the first item.

var data = ["130,839.9,855,837.3,848.65,3980489", "129,875,875,828.1,833.25,6926078", "138,891.3,893.3,865.2,868.75,5035618"],
    result = data
        .map(s => s.split(',').map(Number))
        .sort((a, b) => a[0] - b[0]);
        
console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

var testArray = ["130,839.9,855,837.3,848.65,3980489","129,875,875,828.1,833.25,6926078","138,891.3,893.3,865.2,868.75,5035618"];

const output = [];
for (let i = 0; i < testArray.length; i++) {
    var numbers = testArray[i].split(',');
    for (let j = 0; j < numbers.length; j++) {
        numbers[j] = +numbers[j];
    }
    output[i] = numbers;
}
output.sort(function(x, y) {
    return x[0] - y[0];
});

or shorter

output = testArray.map(s => s.split(',')).map(e => e.map(n => +n)).sort((x, y) => x[0] - y[0]);

First convert each of the Strings to an array of floats values using Array.map() and parseFloat(). After that you can simply sort the array of arrays using Arrays.sort()

Try the following :

var arr = ["130,839.9,855,837.3,848.65,3980489","129,875,875,828.1,833.25,6926078","138,891.3,893.3,865.2,868.75,5035618"];

var result = arr.map((a)=> a.split(",").map((b)=>parseFloat(b))).sort((a,b)=> a[0] -b[0]);
console.log(result);