I am reading some JSON into a 2D JS object as follows:

$.getJSON("file.json", function(arr) {
    dict = arr;
});

Example when I do console.log(dict[1]); - there are thousands of such rows:

{
    "ortho": "a",
    "phon": "a",
    "lemme": "a",
    "cgram": "NOM",
    "genre": "m",
    "nombre": "",
    "freqlemfilms2": "81.36",
    "freqlemlivres": "58.65",
    "freqfilms2": "81.36",
    "_freqlivres": "58.65",
    "_infover": "",
    "_nbhomogr": "3",
    "_nbhomoph": "9",
    "_islem": "1",
    "_nblettres": "1",
    "_nbphons": "1",
    "_cvcv": "V",
    "_p_cvcv": "V",
    "_voisorth": "25",
    "_voisphon": "20",
    "_puorth": "1",
    "_puphon": "1",
    "_syll": "a",
    "_nbsyll": "1",
    "_cv-cv": "V",
    "_orthrenv": "a",
    "_phonrenv": "a",
    "_orthosyll": "a",
    "_cgramortho": "NOM,AUX,VER",
    "_deflem": "",
    "_defobs": "",
    "_old20": "1",
    "_pld20": "1",
    "_morphoder": "a",
    "_nbmorph": "1",
    "no": "1"
}

I'm then trying to filter this to yield all rows (result) where orth is a particular value.

const asArray = Object.entries(dict);
const result = asArray.filter(word => word.ortho === 'a');
console.log(result);

This yields an empty array although I know there are several results. Please could someone advise what I've missed out? Thanks!

CodePudding user response：

The problem is in your use of Object.entries(). Object.entries returns an array of [key, value] tuples, so your filter callback doesn't make sense as it is. (It is trying to access ortho on an array...[1, {"ortho": "a", "phon": "a", ... }].ortho)

Instead, if dict is an object, you need to filter the dict values.

const dict = { 1: {"ortho": "a", "phon": "a", }, 2: {"ortho": "a", "phon": "a",},}

const result = Object.values(dict).filter(word => word.ortho === 'a');

const dict = { 1: { ortho: 'a', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm', nombre: '', }, 2: { ortho: 'g', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm', }, 3: { ortho: 'b', phon: 'a', lemme: 'a', cgram: 'NOM', }, };

const result = Object.values(dict).filter((word) => word.ortho === 'a');

console.log(result);

I've only guessed that dict is an object from your inferences, if it is actually an array, then just filter it directly.

const dict = [ {"ortho": "a", "phon": "a", }, {"ortho": "a", "phon": "a",},]

const result = dict.filter((word) => word.ortho === 'a');

const dict = [ { ortho: 'a', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm', nombre: '' }, { ortho: 'a', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm' }, { ortho: 'b', phon: 'a', lemme: 'a', cgram: 'NOM' },];

const result = dict.filter((word) => word.ortho === 'a');

console.log(result);

Edit (In response to your comment re: filtering by an array)

If you want to filter for multiple values you can declare an array and use Array#includes() to check if the value is included.

const dict = [ {"ortho": "a", "phon": "a", }, {"ortho": "a", "phon": "a",},];

const filter_array = ['a', 'c'];
const result = dict.filter((word) => filter_array.includes(word.ortho));

const dict = [
  { ortho: 'a', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm', nombre: '' },
  { ortho: 'b', phon: 'b', lemme: 'a', cgram: 'NOM', genre: 'm' },
  { ortho: 'c', phon: 'c', lemme: 'a', cgram: 'NOM' },
  { ortho: 'd', phon: 'd', lemme: 'a', cgram: 'NOM' },
];

const filter_array = ['a', 'c'];
const result = dict.filter((word) => filter_array.includes(word.ortho));

console.log(result);

Or, if you wanted to also specify the properties to you could declare an array of [key, value] tuples to check against in your filter call. Here using Array#some() which will match if any matches are found, but you could replace it with Array#every() if you wanted only elements that match all conditions.

const dict = [ {"ortho": "a", "phon": "a", }, {"ortho": "a", "phon": "a",},]


const filter_tuples = [['ortho', 'a'],['phon', 'b'],];
const result = dict.filter((word) => filter_tuples.some(([k, v]) => word[k] === v));

const dict = [
  { ortho: 'a', phon: 'a', lemme: 'a', cgram: 'NOM', genre: 'm', nombre: '' },
  { ortho: 'b', phon: 'b', lemme: 'a', cgram: 'NOM', genre: 'm' },
  { ortho: 'c', phon: 'c', lemme: 'a', cgram: 'NOM' },
  { ortho: 'd', phon: 'd', lemme: 'a', cgram: 'NOM' },
];

const filter_tuples = [['ortho', 'a'],['phon', 'b'],];
const result = dict.filter((word) => filter_tuples.some(([k, v]) => word[k] === v));

console.log(result);