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Is log(n!) = Θ(n·log(n))?
...) >= n/2 * log(n/2) = Omega(n log n).
– Keith Randall
Jan 19 '10 at 22:40
2
@Keith: I don't ge...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
Scala 2.8 breakOut
...breakOut itself. It is of type CanBuildFrom[Nothing,T,To]. We already know all these types, so we can determine that we need an implicit of type CanBuildFrom[Nothing,(Int,String),Map[Int,String]]. But is there such a definition?
Let's look at CanBuildFrom's definition:
trait CanBuildFrom[-From, -E...
Timer function to provide time in nano seconds using C++
...psets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states:
QueryPerformanceCounter() and
QueryPerformanceFrequency() offer a
bit better resolution, but have
different issues. ...
How to use the PI constant in C++
...
On some (especially older) platforms (see the comments below) you might need to
#define _USE_MATH_DEFINES
and then include the necessary header file:
#include <math.h>
and the value of pi can be accessed via:
M_PI
In my math....
How to exit from Python without traceback?
...
If sys.exit() is called in "main program stuff", the code above throws away the value passed to sys.exit. Notice that sys.exit raises SystemExit and the variable "e" will contain the exit code.
– bstpierre
...
What's the _ underscore representative of in Swift References?
...ng, s2: String) -> String {
return s1 + s2;
}
}
When you call foo(), it is called like bar.foo("Hello", s2: "World").
But, you can override this behavior by using _ in front of s2 where it's declared.
func foo(s1: String, _ s2: String) -> String{
return s1 + s2;
}
Then, w...
Regular expression to find URLs within a string
...
It's 2017, and unicode domain names are all over the place. \w may not match international symbols (depends on regex engine), the range is needed instead: a-zA-Z0-9\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF.
– Michael Antipin
Aug...
Debugging in Clojure? [closed]
...
There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (f...
Big-O summary for Java Collections Framework implementations? [closed]
...:
Collections Overview has a nice summary table.
Annotated Outline lists all of the implementations on one page.
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