javascript leave max 3 occurrences of the same obj in an array

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If I populate an array of pairs (inside a get json) like so:

var arrItems = [];
for (let y=0; y<50 ;y++){
    var titl = data.item[y].name;
    var img = data.item[y].image[0].url;
    arrItems.push({t:titl,i:img});
}

How can I then filter it to leave only 3 pairs where value is the same?

Example:

arrItems = [
    {t:one,i:square.jpg},
    {t:two,i:square.jpg},
    {t:three,i:square.jpg},
    {t:four,i:square.jpg},
    {t:five,i:triangle.jpg}
];

Becomes

arrItems = [
    {t:one,i:square.jpg},
    {t:two,i:square.jpg},
    {t:three,i:square.jpg},
    {t:five,i:triangle.jpg}
];

Both JavaScript or jQuery are OK.

You could take a hash table and count the occurences of the wanted property and filter with a max value.

var items = [{ t: 'one', i: 'square.jpg' }, { t: 'two', i: 'square.jpg' }, { t: 'three', i: 'square.jpg' }, { t: 'four', i: 'square.jpg' }, { t: 'five', i: 'triangle.jpg' }],
    count = {},
    result = items.filter(({ i }) => {
        count[i] = (count[i] || 0) + 1;
        return count[i] <= 3;
    });

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

Array.from(), 问题: If I populate an array of pairs (inside a get json) like so: var arrItems = []; for ( let y=0; y<50 ;y++){ var titl = data.item[y].name; var img� JavaScript JS Array. The max() method returns the number with the highest value. Tip: The min() method returns the number with the lowest value. Browser Support.

There might be some more efficient ways to write it, but I would think the easiest to understand is the straightforward iteration with counting:

var counts = {};
for (var i = 0; i < arrItems.length; i++) {
    var item = arrItems[i];
    var count = counts[item.i] || 0;
    if (count >= 3) {
        arrItems.splice(i, 1);
        i--;
    } else {
        counts[item.i] = ++count;
    }
}

Data Structures: Objects and Arrays :: Eloquent JavaScript, console.log(Array.from([1, 2, 3], x => x + x));. 5 has the same result as Array. from( obj ).map( mapFn , thisArg ) , are "inherited" by subclasses of Array , and create new instances of the subclass, not Array . var toLength = function (value) { var len = toInteger(value); return Math.min(Math.max(len, 0),� Because MAX_VALUE is a static property of Number, you always use it as Number.MAX_VALUE, rather than as a property of a Number object you created. Examples Using MAX_VALUE. The following code multiplies two numeric values. If the result is less than or equal to MAX_VALUE, the func1 function is called; otherwise, the func2 function is called.

You can use reduce function

    var arrItems = [
        {t:'one',i:'square.jpg'},
        {t:'two',i:'square.jpg'},
        {t:'three',i:'square.jpg'},
        {t:'four',i:'square.jpg'},
        {t:'five',i:'triangle.jpg'}
    ];

    var output = arrItems.reduce((acc, {t,i})=>{
        acc['mem'][i] = (acc['mem'][i] || 0) + 1;
        acc['mem'][i] <= 3 ? acc['output'].push({t, i}) : ''; 
        return acc;
    }, {'mem':{}, 'output':[]});

console.log(output);

The 10 Most Common Mistakes JavaScript Developers Make, The irregular occurrences of the transformation make him suspect that they Say , for example, that we want to represent a collection of the numbers 2, 3, 5, 7, and 11. In the second, we access the property named max in the Math object ( which is a The object1 and object2 bindings grasp the same object, which is why� JavaScript Datetime: Exercise-11 with Solution. Write a JavaScript function to get the maximum date from an array of dates. Test Data: console.log(max_date(['2015/02/01', '2015/02/02', '2015/01/03'])); Output: "2015/02/02" Sample Solution:-HTML Code:

PHP array_search() Function, If you need help figuring out why your JavaScript isn't working, consult this list of the have witnessed the proliferation of a wide array of powerful JavaScript- based to occur, so we'll just highlight a couple of their more common occurrences. important that they both get the same object, even if priorThing gets assigned� It adds each num (number) in the array to the total value. The 0 at the end of the callback indicates the initial value for total. Starting with 1, the reduce() method adds 1 to the total then moves on to the next value in the array (1 + 0). 2 is added to total (2 + 1). 3 is added to total (3 + 3), and the value of total (6) is returned

Node.js v14.6.0 Documentation, The array_search() function search an array for a value and returns the key. When set to true, the number 5 is not the same as the string 5 (See example 2)� The problem with Math.min() is it expects each parameter to be input separately and cannot take an array of multiple numbers as input. To illustrate this, take a look at the code below: Math.min(1,2,3,4) // 1 Math.min([1,2,3,4]) // NaN. As you can see, Math.min() only works when each number is input as a separate parameter.

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