How get the total sum of NSNumber's from a NSArray?

Question

I have a large NSArray containing NSNumbers like 3, 4, 20, 10, 1, 100, etc...

How do I get the total sum of all these NSNumbers (3 + 4 + 20 + 10 + 1 + 100 + etc...) as one total NSInteger?

Thank you!

Affiance

Answer 1

You can use this:

NSArray* numbers = //array of numbers
NSNumber* sum = [numbers valueForKeyPath: @"@sum.self"];

Feral

This is the most elegant solution. Docs here:developer.apple.com/library/ios/ipad/#documentation/cocoa/… – Rubeola

This is definitely the most elegant solution. However there's a small problem. If one of the elements in the array is NSNull, it crashes. – Ats

Also it's documented to do all arithmetic with doubles. So, five years later, with the 64-bit runtime and NSInteger now being the same size as a double, that risks loss of precision when numbers are large. – Inulin

Does anyone know how to perform those @sum.self in Swift? – Retroact

This also suffers from poor performance if the array has 1000s of numbers. Better to use fast-enumeration instead – Intercontinental

Answer 2

NSInteger sum = 0;
for (NSNumber *num in myArray) {
  sum += [num intValue];
}

Poulter

Answer 3

long long sum = ((NSNumber*)[array valueForKeyPath: @"@sum.longLongValue"]).longLongValue;

Barrington

valueForKeyPath: returns an object, not an integer. – Leftwich

Answer 4

Iterate through the array

int count = [array count];
NSInteger sum = 0;
for (int i = 0; i < count; i++) {
    sum += [[array objectAtIndex:i] integerValue];
}

Counterintelligence

Answer 5

[[numbersArray valueForKeyPath:@"@sum.self"] integerValue]

Explicative

Answer 6

int total = 0;
for (NSNumber *number in array)
{
  total += [number intValue];
}

may this will help you

Shamefaced