Javascript/Typescript update data from one nested array in another

Question

My initial array is like this:

 preData = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];

The array with values is like this:

preData = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

I would like to update the values of first array from the second one, the result:

  finalData= [
        ['APP_NOT_RUNNING', 2],
        ['FALLBACK', 0],
        ['IDLE', 3],
        ['OUTOFSERVICE', 0]
    ];

I would appreciate any help

Mohammad Usman · Accepted Answer · 2019-01-17 06:44:17Z

2

You can use Map() and .forEach() method of arrays:

let arr1 = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];

let arr2 = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

let updateArray = (a1, a2, map = new Map()) => {
  a1.forEach(arr => map.set(arr[0], arr));
  a2.forEach(arr => map.set(arr[0], arr));
  
  return [...map.values()];
};

console.log(updateArray(arr1, arr2));

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answered Jan 17, 2019 at 6:44

Mohammad Usman

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Comments

Aleksey L. · Accepted Answer · 2019-01-17 08:33:41Z

1

One of the possible solutions would be converting initial array to Map, updating it and converting it back to array:

const preData = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];

const valueData = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

const map = new Map(preData);

for (const [key, value] of valueData) {
    map.set(key, value);
}

const result = Array.from(map);
console.log(result);

Update - typings could be:

const preData: ReadonlyArray<[string, number]> = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];

const valueData: Array<[string, number]> = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

edited Jan 17, 2019 at 8:33

answered Jan 17, 2019 at 6:44

Aleksey L.

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1 Comment

Gyuzal Over a year ago

Thanks for your reply, but how can I fix error: Argument of type '(string | number)[][]' is not assignable to parameter of type 'ReadonlyArray<[any, any]>' when building the release?

Amardeep Bhowmick · Accepted Answer · 2019-01-17 06:42:08Z

0

Match the the second array actualData content of index '0' with the original array preData index '0'. If it is a match, copy over that content from index '1' (the value) of actualData into the original array.

var preData = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];
var actualData = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

preData.forEach((ele, idx, arr) =>{
        actualData.forEach(item =>{
                       if(item[0] === ele[0]){
                           ele[1] = item[1];
                           arr[idx] = ele;
                        }
                   });
});
console.log(preData);

answered Jan 17, 2019 at 6:42

Amardeep Bhowmick

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Comments

Hussain Ali Akbar · Accepted Answer · 2019-01-17 06:46:44Z

You will need to iterate over the preData array and check if a value exists for each value in the actualData array or not. If it doesnt, just push the default valye to the finalData array and if it does, add the value and then push it.

use forEach to iterate over the preData array and use filter to check if the data exists for each value in preData.

    const preData = [
      ['APP_NOT_RUNNING', 0],
      ['FALLBACK', 0],
      ['IDLE', 0],
      ['OUTOFSERVICE', 0]
    ];
    
    const actualData = [
      ['APP_NOT_RUNNING', 2],
      ['IDLE', 3],
    ];
    
    const finalData = [];
    
    preData.forEach(preDataValue => {
      const index = finalData.push(preDataValue);
      const data = actualData.filter(d => d[0] === preDataValue[0]);
      if (data.length) {
        finalData[index-1][1] += data[0][1];
      }
    });

    console.log(finalData);

Jagdish Idhate · Accepted Answer · 2019-01-17 06:47:43Z

0

We can use .map & .find

preData = [
    ['APP_NOT_RUNNING', 0],
    ['FALLBACK', 0],
    ['IDLE', 0],
    ['OUTOFSERVICE', 0]
];

preData2 = [
    ['APP_NOT_RUNNING', 2],
    ['IDLE', 3],
];

const finalData = preData.map(x=>{
  const found = preData2.find(y=>y[0]===x[0])
  if(found)
    x[1] = found[1]
  return x;
})

console.log(finalData);

answered Jan 17, 2019 at 6:47

Jagdish Idhate

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