Sorting Array in increasing order

Question

I have an array that contains values like 0,3,2,8 etc.I want to sort my array in increasing order.Please tell me how to do this.

Thanks in advance!!

Solution 1

If your array is an NSArray containing NSNumbers:

NSArray *numbers = [NSArray arrayWithObjects:
                    [NSNumber numberWithInt:0],
                    [NSNumber numberWithInt:3],
                    [NSNumber numberWithInt:2],
                    [NSNumber numberWithInt:8],
                    nil];

NSSortDescriptor* sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:nil ascending:YES selector:@selector(localizedCompare:)];
NSArray *sortedNumbers = [numbers sortedArrayUsingDescriptors:[NSArray arrayWithObject:sortDescriptor]];

Keep in mind though, that this is just one way to sort an NSArray.

Just to name a few other methods of NSArray:

• sortedArrayHint
• sortedArrayUsingFunction:context:
• sortedArrayUsingFunction:context:hint:
• sortedArrayUsingDescriptors:
• sortedArrayUsingSelector:
• sortedArrayUsingComparator:
• sortedArrayWithOptions:usingComparator:

---

If your array is a c int array containing ints:

#include <stdio.h>
#include <stdlib.h>
int array[] = { 0, 3, 2, 8 };
int sort(const void *x, const void *y) {
    return (*(int*)x - *(int*)y);
}
void main() {
    qsort(array, 10, sizeof(int), sort);
}

Solution 2

You don't need a sort descriptor if your array is that simple with NSNumbers only. If it's called array, then

[array sortedArrayUsingSelector:@selector(compare:)];

will return a new array sorted in increasing order, as you want.

Solution 3

NSSortDescriptor *sortDescriptor;
sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:nil
                                              ascending:YES] autorelease];
NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
NSArray *sortedArray;
sortedArray = [**YourArray** sortedArrayUsingDescriptors:sortDescriptors];

Solution 4

Use the code: [[myData allKeys]sortedArrayUsingSelector:@selector(psuedoNumericCompare:)];

myData is your array. If you use that line in your code, it will sort on size of the integer (and not alphabetic, so it won't sort like 1, 111, 2,322, 333, 4445, 45, 67 but like 1, 2, 45, 67, 111, 322, 333, 4445).

Original source: How to let the sortedArrayUsingSelector using integer to sort instead of String?

Solution 5

Sorting has many solutions, each with different efficiencies.

The easiest and most natural sort, in my opinion, is insertion sort. Go to this page and scroll down to look at the code. Insertion sort

For a more complete list of all of the sorting algorithms, check this page

View more solutions

Comments

[James P]

psuedoNumericCompare isn't a method on NSString, you'll have to add it yourself.