Sort negative number string in iOS with NSStringCompareOptions - ios

Question

I am trying to sort some list of strings. And names of elements could be almost anything, from real names, strings, dates,... and numbers.
I found NSStringCompareOptions with NSNumericSearch, wich work fast enough and it work nice so :
[1,2,21,3,55,6] --> [1,2,3,6,21,55]
But my problems are negative numbers
[1,2,3,-1,-4,-5] --> [-1,-4,-5,1,2,3]
What it is not right.
I know that Apple stays :
Numeric comparison only applies to the numerals in the string,
not other characters that would have meaning in a numeric representation
such as a negative sign, a comma, or a decimal point.
But my question is how to achieve this, because I know I am not only who do this.
EDIT :
Thanks to Narendra Pandey, but my real case is a little bit complicated, so his answer can't be used here.
So let say I have some dictionary with numbers as keys and strings as values :
dic = {#1:#"123", #2:#"-123", #5:"MyName",...};
then I have array of object with ids.
array = #[{object with id 5}, {object with id 2},...];
and I need sorted array of object by name of properties.
NSStringCompareOptions comparisonOption = NSCaseInsensitiveSearch | NSNumericSearch;
array = [array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
NSString * name1 = [dic objectForKey:obj1.someId];
NSString * name2 = [dic objectForKey:obj2.someId];
return [name1 compare:name2 options:comparisonOption];;
}];
EDIT 2:
Maybe I should state that I have solution, but it is 4 times slower that sorting with NSStringCompareOptions
// CHECK IF IT IS NUMBER
NSNumber * number1 = [numberFormatter numberFromString:string1];
NSNumber * number2 = [numberFormatter numberFromString:string2];
//
// NSLog(#"NUMBERS : %#, %#", number1, number2);
if (number1 && number2) {
return [number1 compare:number2];
}
return [string1 compare:string2 options:comparisonOption];

Answer 1

NSArray * numbers = #[#1, #2, #3, #-4, #-5, #6, #9];
NSPredicate * predicateForPositive = [NSPredicate predicateWithFormat:#"integerValue >= 0"];
NSArray * positiveNumbers = [numbers filteredArrayUsingPredicate:predicateForPositive];
NSPredicate * predicateForNegative = [NSPredicate predicateWithFormat:#"integerValue <= 0"];
NSArray * NegativeNumber = [numbers filteredArrayUsingPredicate:predicateForNegative];
NSLog(#"Negative number %#",NegativeNumber);
NSLog(#"Positive number %#",positiveNumbers);
Output:
Negative number (
"-4",
"-5"
)
Positive number (
1,
2,
3,
6,
9
)
Now sort both and concate both Array.

Answer 2

Thanks to Narendra Pandey I found solution for me.
Let me state first that Narendra Pandey solution works, but it is slower, even 3 times.
(in my case 0.014s with NSStringCompareOptions, and 0,042 Narendra Pandey solution).
But if I use his idea and change it a little bit :
array = [array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
NSString * name1 = somehow get string1;
NSString * name2 = somehow get string2;
if ([string1 integerValue] <0 && [string2 integerValue]<0) {
return - [string1 compare:string2 options:comparisonOption];
}
return [string1 compare:string2 options:comparisonOption];
}];
this method is faster, in my case 0,015s which is comparable with NSStringCompareOptions.
In this way you avoid to go through whole array at beginning to separate negative and positive numbers, and then sort them.

Answer 3

This function get any array and convert it to sorted Double array
var numberArray: [Any] = [4, 3.9, -23,3, 7.6, -51, 75.3, "0", "-(22)"]
/// This function get any array and convert it to sorted _Double_ array
/// - Note: Non-numerical elements are automatically removed from the array
/// - Parameters:
/// - numbers: array of anything
/// - Returns: sorted _Double_ array
func sortAnyNumbers(_ numbers: [Any]) -> [Double] {
var _numbers: [Double] = []
numbers.forEach { number in
// Delete non-numeric characters
if let numb = Double("\(number)".components(separatedBy: CharacterSet(charactersIn: "-01234567890.").inverted).joined()) {
_numbers.append(numb)
}
}
return _numbers.sorted()
}
print(sortAnyNumbers(numberArray)) //[-51.0, -23.0, -22.0, 0.0, 3.0, 3.9, 4.0, 7.6, 75.3]