find number of "yes" in NSMutableArray

Question

Let's say I have NSMutableArray as below.

(
        {
        blockNumber = 1;
        boxId = 1;
        boxNumber = 4536;
        carId = 10;
        carNumber = 10;
        isDeleted = yes;
    },
        {
        blockNumber = 2;
        boxId = 2;
        boxNumber = 4537;
        carId = 10;
        carNumber = 10;
        isDeleted = yes;
    },
        {
        blockNumber = 3;
        boxId = 3;
        boxNumber = 4538;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 4;
        boxId = 4;
        boxNumber = 4539;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 5;
        boxId = 5;
        boxNumber = 4540;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 6;
        boxId = 6;
        boxNumber = 4541;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 7;
        boxId = 7;
        boxNumber = 4542;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 8;
        boxId = 8;
        boxNumber = 4543;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 9;
        boxId = 9;
        boxNumber = 4544;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 10;
        boxId = 10;
        boxNumber = 4545;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 11;
        boxId = 11;
        boxNumber = 4546;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 12;
        boxId = 12;
        boxNumber = 4547;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 13;
        boxId = 13;
        boxNumber = 4548;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 14;
        boxId = 14;
        boxNumber = 4549;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 15;
        boxId = 15;
        boxNumber = 4550;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 16;
        boxId = 16;
        boxNumber = 4551;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 17;
        boxId = 17;
        boxNumber = 4552;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 18;
        boxId = 18;
        boxNumber = 4553;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 19;
        boxId = 19;
        boxNumber = 4554;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 20;
        boxId = 20;
        boxNumber = 4555;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 21;
        boxId = 21;
        boxNumber = 4556;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 22;
        boxId = 22;
        boxNumber = 4557;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 23;
        boxId = 23;
        boxNumber = 4558;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 24;
        boxId = 24;
        boxNumber = 4559;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 25;
        boxId = 25;
        boxNumber = 4560;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 26;
        boxId = 26;
        boxNumber = 4561;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 27;
        boxId = 27;
        boxNumber = 4562;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 28;
        boxId = 28;
        boxNumber = 4563;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 29;
        boxId = 29;
        boxNumber = 4564;
        carId = 10;
        carNumber = 10;
        isDeleted = no;
    },
        {
        blockNumber = 30;
        boxId = 30;
        boxNumber = 4565;
        carId = 10;
        carNumber = 10;
        isDeleted = yes;
    }
)

What I want is number that will be me isDeleted = yes.

In my case, it is 3.

I know I can do this by looping like below.

for (NSMutableDictionary* aDict in carBoxesArray) {
    if ([aDict[@"isDeleted"] isEqualToString:@"yes"]) {
        findTotalYes++;
    }
}

However I am looking any another way (may be one liner) which will give me what I want.

Especially I don't want to use loop (as I can have more number of records in array which will take time in iteration)

*Any* solution (explicit loop, predicate, Key-Value Coding) has to iterate over all elements. An explicit loop is probably the fastest solution. See http://stackoverflow.com/a/21158730/118741 or http://stackoverflow.com/a/15931719/1187415 for some comparisons. — Martin R, Mar 12 '14 at 10:23

βhargavḯ · Accepted Answer · 2014-03-12T10:14:49.327

4

You can use NSPredicate

NSArray *totalYes = [carBoxesArray filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"(isDeleted == %@)", @"yes"]];

NSLog(@"Found Total YES: %d",totalYes.count);

edited Mar 12 '14 at 10:14

answered Mar 12 '14 at 10:04

βhargavḯ

9,786
1
37
59

score 0 · Answer 2 · answered Mar 12 '14 at 10:05

0

You can use loop in background thread and use some loader in main thread. In this case display will not freeze when you are doing looping.

answered Mar 12 '14 at 10:05

aparesidam

309
2
13

score 0 · Answer 3 · answered Mar 12 '14 at 10:13

You can use NSCountedSet as well :

NSCountedSet *countset = [NSCountedSet setWithArray:[carBoxesArray valueForKey:@"isDeleted"]];
NSInteger count = [countset countForObject:@"yes"];

As you asked for one liner, merge the above two lines to one:

NSInteger count = [[NSCountedSet setWithArray:[carBoxesArray valueForKey:@"isDeleted"]] countForObject:@"yes"];

score 0 · Answer 4 · answered Mar 12 '14 at 10:24

0

u can also use enumeration,

like below

__block int count = 0;
[carBoxesArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
   if([[obj objectForKey:@"isDeleted"] isEqualToString:@"yes"])
       count++;
}];

NSLog(@"%d",count);

answered Mar 12 '14 at 10:24

Shankar BS

8,394
6
41
53

Block enumeration is (slightly) slower than fast enumeration, see e.g. http://blog.bignerdranch.com/2337-incremental-arrayification/. – Martin R Mar 12 '14 at 10:26
yup, i saw, i posted an alternate answer ... :) – Shankar BS Mar 12 '14 at 10:28

find number of "yes" in NSMutableArray

4 Answers4