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iphone - Sort an NSArray in Descending Order

I have an NSArray of NSNumber objects that I have successfully sorted in ascending order using the following:

[myArray sortedArrayUsingSelector:@selector(compare:)]

However, I need to sort this in descending order. I take it that compare: only sorts in ascending order. While I can go about reversing the NSArray, I am curious as to whether or not there is a more simpler or more effective way of going about doing this.

EDIT: I found this question which provides a simple way to reverse iterate an NSArray:

for (id someObject in [myArray reverseObjectEnumerator])

This works fine, I guess it's a nice simple solution, but I'm curious as to whether or not there is a way to specify sorting in descending order.

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Use a sort descriptor

NSSortDescriptor* sortOrder = [NSSortDescriptor sortDescriptorWithKey: @"self" 
                                                            ascending: NO];
return [myArray sortedArrayUsingDescriptors: [NSArray arrayWithObject: sortOrder]];

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