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Select N random elements from a List in C#
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@recursive: The proof is almost trivial. We know how to select K items out of K for any K and how to select 0 items out of N for any N. Assume we know a method to uniformly select K or K-1 items out of N-1 >= K; then we can select K items out of N by selecting the fi...
How can I make the tabs work normally on Xcode 4?
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UPDATE for 2020:
Finally, almost 10 years later, Xcode 12 beta 3 now appears to mostly resolve the issue described here. There is a new Navigation Style option in the Navigation settings panel that controls this behavior.
Of course, this may change in subsequent betas or the final release ...
How can I get the SQL of a PreparedStatement?
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It's nowhere definied in the JDBC API contract, but if you're lucky, the JDBC driver in question may return the complete SQL by just calling PreparedStatement#toString(). I.e.
System.out.println(preparedStatement);
At least MyS...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
Git has a well-known, or at least sort-of-well-known, empty tree whose SHA1 is:
3 Answers
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How remove word wrap from textarea?
...ut you can set wrap="soft" to explicitly disable wrap:
<textarea name="nowrap" cols="30" rows="3" wrap="soft"></textarea>
EDIT: The "wrap" attribute is not officially supported. I got it from the german SELFHTML page (an english source is here) that says IE 4.0 and Netscape 2.0 suppor...
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
...guaranteed to remember insertion order. "The order of elements in **kwargs now corresponds to the order in which keyword arguments were passed to the function." - docs.python.org/3/whatsnew/3.6.html In fact, all dicts in CPython 3.6 will remember insertion order as an implementation detail, this bec...
Numpy where function multiple conditions
...ue, False, False, False, False, False,
False, False], dtype=bool)
Now you can call np.where on the combined boolean array:
In [239]: np.where((dists >= r) & (dists <= r + dr))
Out[239]: (array([10, 11, 12]),)
In [240]: dists[np.where((dists >= r) & (dists <= r + dr))]
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What is the best way to filter a Java Collection?
...ill cannot believe I am collecting SO points for this answer. At any rate, now that Java 8 has introduced closures to the language, my answer would now be considerably different, and simpler. With Java 8, there is no need for a distinct static utility class. So if you want to find the 1st element th...
How to write iOS app purely in C
...plicationMain(int, ...);
// Entry point of the application. If you don't know what this is by now,
// then you probably shouldn't be reading the rest of this post.
int main(int argc, char *argv[])
{
// Create an @autoreleasepool, using the old-stye API.
// Note that while NSAutoreleasePoo...
Get list of databases from SQL Server
...ute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you prefer
EXEC sp_databases
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