Suppose I have an array of dictionaries:
[ { "id": 2 }, { "id": 59 }, { "id": 31 } ... ]
How can I sort this so that it's in descending order, sorted by "id"?
My initial approach is something like:
Loop through each element, find the biggest one, and put it into a new array. Then, remove that from the element. Repeat.
But I know that's wrong and not efficient.
You can use the sort function in Swift. Something like this:
let arr = [["id": 2], ["id": 59], ["id": 31]]
let sortedArr = arr.sort { Int($0["id"]!) > Int($1["id"]!) }
arr.sort{$0.0["id"] > $0.1["id"] }
arr.sort(by: >) apple.co/2FqkBLlYou have only need to use below code that will give you the sorted array using the sort because dictionary is also a collection class.
let sortedDict = wordDict.sort { $0.0 < $1.0 }
print("\(sortedDict)") //
In above code you found the sorted Dictionary. For sorting Array you need to add below code.
let sortedArr = arr.sort { Int($0["id"]!) > Int($1["id"]!) }
I don't know if it is the fastest or the better,but swift provides the sort method that takes a clojure as an argument. You can write something like that:
var ordered = arrdict.sort { (dic1, dic2) -> Bool in
dic1["id"] > dic2["id"]
}
Or compact:
var ordered = arrdict.sort { $0["id"] > $1["id"] }
The $0..x makes possible to access clojure arguments.
About sort algorithm Apple write:
Discussion The sorting algorithm is not stable (can change the relative order of elements that compare equal).
Requires: The less-than operator (func <) defined in the Comparable conformance is a strict weak ordering over the elements in self.
var val = [ { "id": 2 }, { "id": 59 }, { "id": 31 }];
var a = new Array();
for (i = 0; i < val.length; i++) {
document.write(Object.keys(val[i]).map(function (key) {return val[i][key]})+"<br>");
a.push(Object.keys(val[i]).map(function (key) {return val[i][key]}));
}
a.sort();
var result = new Array();
for (i = 0; i < val.length; i++) {
result.push({"id": a[i]});
}
