duplicates

I have an XML document I generate on the fly, and I need a function to eliminate any duplicate nodes from it. My function looks like: declare function local:start2() { let $data := local:scan_books() return <books>{$data}</books> }; Sample output is: <books> <book> <title>XML in 24 hours</title> <author>Some Guy</author> </book> <book> <title>XML in 24 hours</title> <author>Some Guy</author> </book> </books> I want just the one entry in my books root tag, and there are other tags, like say pamphlet in there too that need to have duplicates removed. Any ideas? Updated following comments. By

Value of my NSArray includes the duplicates. I find the duplicates but now how can I find the no. they repeat? You can use NSCountedSet for this. Add all your objects to a counted set, then use the countForObject: method to find out how often each object appears. Example: NSArray *names = [NSArray arrayWithObjects:@"John", @"Jane", @"John", nil]; NSCountedSet *set = [[NSCountedSet alloc] initWithArray:names]; for (id item in set) { NSLog(@"Name=%@, Count=%lu", item, (unsigned long)[set countForObject:item]); } You can try something like this __block NSInteger elementCount = 0; NSArray *array;

I have a vector with repeated elements, and would like to remove them so that each element appears only once. In Python I could construct a Set from a vector to achieve this, but how can I do this in R? sus_mlm You can check out unique function. > v = c(1, 1, 5, 5, 2, 2, 6, 6, 1, 3) > unique(v) [1] 1 5 2 6 3 This does the same thing. Slower, but useful if you also want a logical vector of the duplicates: v[duplicated(v)] To remove contiguous duplicated elements only, you can compare the vector with a shifted version of itself: v <- c(1, 1, 5, 5, 5, 5, 2, 2, 6, 6, 1, 3, 3) v[c(TRUE, !v[-length