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Best practice? - Array/Dictionary as a Core Data Entity Attribute [closed]
...n be handled by Core Data.
Update
As of OS X 10.7, Core Data includes an ordered set type which can be used in place of an array. If you can target 10.7 or later, this is the best solution for ordered (array-like) collections.
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What's the fastest way to merge/join data.frames in R?
...- data.frame(d1, g1, g2)
library(rbenchmark)
benchmark(replications = 1, order = "elapsed",
merge = merge(d1, d2),
plyr = join(d1, d2),
data.table = {
dt1 <- data.table(d1, key = "x")
dt2 <- data.table(d2, key = "x")
data.frame( dt1[dt2,list(x,y1,y2=dt2$y2)] )
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What is the largest Safe UDP Packet Size on the Internet
...s inside of another protocol such as IPsec (used for VPNs and the like) in order to route the packet to its destination. So if you do not know the MTU on your particular network path, it is best to leave a reasonable margin for other header information that you may not have anticipated. A 512-byte...
Find kth smallest element in a binary search tree in Optimum way
...doing the operation in O(n), the worst case since I am planning to do an inorder traversal of the entire tree. But deep down I feel that I am not using the BST property here. Is my assumptive solution correct or is there a better one available ?
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Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...orzing the ctx.Database.initialize() of each context to run in the correct order, or run the Update-Database command by hand in the correct order. (And teh reverse, if you do a db migration to previous version). It`s "dangerous" but can be done.
– JotaBe
Nov 24...
How to select only the records with the highest date in LINQ
...q = from n in table
group n by n.AccountId into g
select g.OrderByDescending(t=>t.Date).FirstOrDefault();
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Convert nested Python dict to object?
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Can we guarantee that the order of the list returned by keys() and values() match in order? I mean, if it is a OrderedDict, yes. But a standard dict? I know that CPython 3.6+ and PyPy "compact" dicts are ordered, but quoting documentation: "The order-...
Using Auto Layout in UITableView for dynamic cell layouts & variable row heights
...ll to grow in height. (Of course, you need to get the constraints right in order for this to work correctly!)
Getting your constraints right is definitely the hardest and most important part of getting dynamic cell heights working with Auto Layout. If you make a mistake here, it could prevent every...
Throttling method calls to M requests in N seconds
...happen in big bursts by keeping the size M and delay N relatively small in order of handful millis. eg. M = 5, N = 20ms would provide a through put of 250/sec kepping burst to happen in size of 5.
– FUD
Sep 22 '12 at 10:51
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What is the $$hashKey added to my JSON.stringify result
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and if you have a filter to apply, here is the correct order: item in somelist | filter:somefilter track by item.key, don't write the filter at the end of the line !
– Lewen
Mar 22 '16 at 21:16
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