Swift sorting array of structs by string double

Question

I have an array of structs that I am looking to sort from highest to lowest based on Double value stored as a String. This is the way I\'m currently doing it:

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Answer 1

You can convert the weekFTC string to a Double and then compare, like so:

users.sort { (lhs, rhs) -> Bool in
    let lhsVal = Double(lhs.weekFTC) ?? 0
    let rhsVal = Double(rhs.weekFTC) ?? 0

    return lhsVal > rhsVal
}

---

Comparing strings directly does a lexicographical comparison.

Example:

var array = ["111", "e3", "22"]

array.sort { (lhs, rhs) -> Bool in
    return lhs > rhs
}
print(array) //["e3", "22", "111"]

So we should see if the string can be made into a number and then sort.
This time it will do a numeric comparison, like so:

var array = ["111", "e3", "22"]

array.sort { (lhs, rhs) -> Bool in
    let lhs = Double(lhs) ?? 0
    let rhs = Double(rhs) ?? 0
    return lhs > rhs
}
print(array) //["111", "22", "e3"]

Answer 2

Use a comparator which is able to handle numeric strings

users.sort { $0.weekFTC.compare($1.weekFTC, options: .numeric) == .orderedDescending }