How would I sort this data by count and year values in ascending order prioritizing on the count value?
//sort this
var data = [
{ count: '12', year: '1956' },
{ count: '1', year: '1971' },
{ count: '33', year: '1989' },
{ count: '33', year: '1988' }
];
//to get this
var data = [
{ count: '1', year: '1971' },
{ count: '12', year: '1956' },
{ count: '33', year: '1988' },
{ count: '33', year: '1989' },
];
A simple solution is:
data.sort(function (a, b) {
return a.count - b.count || a.year - b.year;
});
This works because if count is different, then the sort is based on that. If count is the same, the first expression returns 0 which converts to false and the result of the second expression is used (i.e. the sort is based on year).
var data = [
{ count: '12', year: '1956' },
{ count: '1', year: '1971' },
{ count: '33', year: '1989' },
{ count: '33', year: '1988' }
];
console.log(data.sort(function (x, y) {
var n = x.count - y.count;
if (n !== 0) {
return n;
}
return x.year - y.year;
}));You can use JavaScript's .sort() array method (try it out):
data.sort(function(a, b) {
// Sort by count
var dCount = a.count - b.count;
if(dCount) return dCount;
// If there is a tie, sort by year
var dYear = a.year - b.year;
return dYear;
});
Note: This changes the original array. If you need to make a copy first, you can do so:
var dataCopy = data.slice(0);
Based on great @RobG solution, this is a generic function to sort by multiple different properties, using a JS2015 tricky on map + find:
let sortBy = (p, a) => a.sort((i, j) => p.map(v => i[v] - j[v]).find(r => r))
sortBy(['count', 'year'], data)
Also, if you prefer, a traditional JS version (use with caution due to find compatibility in old browsers):
var sortBy = function (properties, targetArray) {
targetArray.sort(function (i, j) {
return properties.map(function (prop) {
return i[prop] - j[prop];
}).find(function (result) {
return result;
});
});
};
you have to work out this problem like this way
var customSort = function(name, type){
return function(o, p){
var a, b;
if(o && p && typeof o === 'object' && typeof p === 'object'){
a = o[name];
b = p[name];
if(a === b){
return typeof type === 'function' ? type(o, p) : o;
}
if(typeof a=== typeof b){
return a < b ? -1 : 1;
}
return typeof a < typeof b ? -1 : 1;
}
};
};
e.g : data.sort(customSort('year', customSort('count')));
user this where 'count'-> first priority and 'year'-> second priority
data.sort(function(a,b){
return a['count']<b['count']?-1:(a['count']>b['count']?1:(a['year']<b['year']?-1:1));
});
If you are looking to sort strings in alphabetical order rather than numbers, here's a sample problem and its solution.
Example Problem: Array of arrays (finalArray) with first entry a folder path and second entry the file name; sort so that array is arranged by folder first, and within identical folders, by file name.
E.g. after sorting you expect:
[['folder1', 'abc.jpg'],
['folder1', 'xyz.jpg'],
['folder2', 'def.jpg'],
['folder2', 'pqr.jpg']]
Refer to Array.prototype.sort() - compareFunction
finalArray.sort((x: any, y: any): number => {
const folder1: string = x[0].toLowerCase();
const folder2: string = y[0].toLowerCase();
const file1: string = x[1].toLowerCase();
const file2: string = y[1].toLowerCase();
if (folder1 > folder2) {
return 1;
} else if (folder1 === folder2 && file1 > file2) {
return 1;
} else if (folder1 === folder2 && file1 === file2) {
return 0;
} else if (folder1 === folder2 && file1 < file2) {
return -1;
} else if (folder1 < folder2) {
return -1;
}
});
Keep in mind, "Z" comes before "a" (capitals first according to Unicode code point) which is why I have toLowerCase(). The problem the above implementation does not solve is that "10abc" will come before "9abc".
Simply do:
array.sort((a,b)=>a[1]-b[1])
Replace 1 inside the brackets depending on the index based on which you need sorting.
To generalize, let me add the snippet below:
array.sort((a,b)=>a[i]-b[i])
I've seen many do this using a full function, which isn't necessary when a simple arrow function can do the job.
Keep it simple!
Thank you.
