Question 53130 in Javascript Question posted in
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Replace values in array based on lookup table – javascript

I have a long array which has shorthand ID’s which I want to replace with the full values from a lookup

Here’s the original array

const original = 
[ [ '18', 'v'],
  [ '20', 'aev'],
  [ '22', 'v'],
  [ '23', 'v'],
  [ '25', 'c'],
  [ '29', 'vv'],
  [ '30', 'c'] ]

The lookup

const lookup = {'v' : 'monkey', 'aev' : 'dog', 'c' : 'cow', 'vv': 'lion'};

The result I want to see

const result = 
[ [ '18', 'monkey'],
  [ '20', 'dog'],
  [ '22', 'monkey'],
  [ '23', 'monkey'],
  [ '25', 'cow'],
  [ '29', 'lion'],
  [ '30', 'cow'] ]

I’m not sure if I should use a map function or for loop and how this would look exactly.

I’ve tried multiple versions of for loops, but I can’t get to the result, because I’m not returning the exact match (it picks up v (monkey) instead of the aev value (dog))

Tags:

3

Answers


  1. 0 
    const original = [ 
  [ '18', 'v'],
  [ '20', 'aev'],
  [ '22', 'v'],
  [ '23', 'v'],
  [ '25', 'c'],
  [ '29', 'vv'],
  [ '30', 'c'] ]

const lookUp = {'v' : 'monkey', 'aev' : 'dog', 'c' : 'cow', 'vv': 'lion'};  

const result = original.map(item => [item[0], lookUp[item[1]]])
console.log(result)
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  2. 0

    You can use map with destructuring syntax

    const original = [
  ['18', 'v'],
  ['20', 'aev'],
  ['22', 'v'],
  ['23', 'v'],
  ['25', 'c'],
  ['29', 'vv'],
  ['30', 'c'],
];

const lookup = { 'v': 'monkey', 'aev': 'dog', 'c': 'cow', 'vv': 'lion' };

const result = original.map(([id, shorthand]) => [id, lookup[shorthand]]);

console.log(result);
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  3. 0

    You can create a new array and push the desired elements on it like this:

    const original = [ 
  [ '18', 'v'],
  [ '20', 'aev'],
  [ '22', 'v'],
  [ '23', 'v'],
  [ '25', 'c'],
  [ '29', 'vv'],
  [ '30', 'c'] ]

const lookUp = {'v' : 'monkey', 'aev' : 'dog', 'c' : 'cow', 'vv': 'lion'};  

const result = [];

original.map((item) => {
  result.push([item[0], lookUp[item[1]]])
})

console.log(result)
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