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Boolean operators && and ||
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350
The shorter ones are vectorized, meaning they can return a vector, like this:
((-2:2) >= 0) ...
SQL Add foreign key to existing column
If I am using the following SQL command in SQL Server 2008 to update a table with a foreign key constraint:
6 Answers
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How does HashSet compare elements for equality?
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edited Feb 1 '18 at 7:10
answered Jan 21 '12 at 9:43
Jon...
Error “initializer element is not constant” when trying to initialize variable with const
... C language, the term "constant" refers to literal constants (like 1, 'a', 0xFF and so on), enum members, and results of such operators as sizeof. Const-qualified objects (of any type) are not constants in C language terminology. They cannot be used in initializers of objects with static storage dur...
Lambda function in list comprehensions
... calls it ten times.
The second one doesn't call the function. It creates 10 different lambda functions. It puts all of those in a list. To make it equivalent to the first you need:
[(lambda x: x*x)(x) for x in range(10)]
Or better yet:
[x*x for x in range(10)]
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Sleep Command in T-SQL?
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Look at the WAITFOR command.
E.g.
-- wait for 1 minute
WAITFOR DELAY '00:01'
-- wait for 1 second
WAITFOR DELAY '00:00:01'
This command allows you a high degree of precision but is only accurate within 10ms - 16ms on a typical machine as it relies on GetTickCount. So, for example, the call W...
count number of lines in terminal output
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answered Sep 17 '12 at 10:32
João SilvaJoão Silva
78.1k2525 gold badges143143 silver badges149149 bronze badges
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Get TransactionScope to work with async / await
...onContext based on this example http://blogs.msdn.com/b/pfxteam/archive/2012/01/20/10259049.aspx .
3 Answers
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Run two async tasks in parallel and collect results in .NET 4.5
... Console.WriteLine("Starting");
var task1 = Sleep(5000);
var task2 = Sleep(3000);
int[] result = await Task.WhenAll(task1, task2);
Console.WriteLine("Slept for a total of " + result.Sum() + " ms");
}
private async static...
PHP Get all subdirectories of a given directory
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answered Mar 26 '10 at 14:58
ghostdog74ghostdog74
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