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How do I find the duplicates in a list and create another list with them?
...firelynx(a):
vc = pd.Series(a).value_counts()
return vc[vc > 1].index.tolist()
def HenryDev(myList):
newList = set()
for i in myList:
if myList.count(i) >= 2:
newList.add(i)
return list(newList)
def yota(number_lst):
seen_set = set()
duplicat...
How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
... NSString *savedSearchTerm_;
NSInteger savedScopeButtonIndex_;
BOOL searchWasActive_;
}
@property (nonatomic, retain) NSManagedObjectContext *managedObjectContext;
@property (nonatomic, retain, readonly) NSFetchedResultsController *fetchedResultsController;
@prope...
What is the difference D3 datum vs. data?
...the same result my looping on the original array and accessing the data by index like so:
data.map((n, i) => {
el
.append('div')
.classed('a', true)
.datum(data)
.text(d => `node-${n} => data: ${d[i]}`);
});
Try it here: https://jsfiddle.net/gleezer/e4m6j2d8/6/
Again, I think t...
Error-Handling in Swift-Language
...nd lines are
not executed because the length property and the characterAtIndex:
method do not exist on an NSDate object. The myLength constant is
inferred to be an optional Int, and is set to nil. You can also use an
if–let statement to conditionally unwrap the result of a method that
th...
Multiple INSERT statements vs. single INSERT with multiple VALUES
...rting would be pointless anyway even if it did).
Moreover if a clustered index is added to the table the plan still shows an explicit sort step so it doesn't seem to be sorting at compile time to avoid a sort at run time.
I tried to look at this in a debugger but the public symbols for my versi...
Evenly distributing n points on a sphere
...g. Note that above I created an offset of my indices by adding 0.5 to each index. This was just visually appealing to me, but it turns out that the choice of offset matters a lot and is not constant over the interval and can mean getting as much as 8% better accuracy in packing if chosen correctly. ...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...nvenient to have the upper bits zeroed, so you can use a value as an array index (because all regs have to be the same size in an effective address: [rsi + edx] isn't allowed). Of course avoiding false dependencies / partial-register stalls (the other answer) is another major reason.
...
Big-O for Eight Year Olds? [duplicate]
.... It doesn't matter if the collection has 10 items or 10000; it's still at index (say) 3, so we just jump to location 3 in memory.
O(n): retrieving an element from a linked list. Here, A = 0.5, because on average you''ll have to go through 1/2 of the linked list before you find the element you're lo...
How do you convert a byte array to a hexadecimal string, and vice versa?
...7.
Some further considerations:
I didn't use a second loop variable to index into c, since measurement shows that calculating it from i is cheaper.
Using exactly i < bytes.Length as upper bound of the loop allows the JITter to eliminate bounds checks on bytes[i], so I chose that variant.
Mak...
var functionName = function() {} vs function functionName() {}
...
(Remember that Array#map passes the entry as the first argument, and the index as the second.)
In both cases, the body of the function is just an expression; the function's return value will automatically be the result of that expression (you don't use an explicit return).
If you're doing more t...