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Nearest neighbors in high-dimensional data?
...a set of test instances (to calculate predicted values) for n=1, n=2, n=3, etc. and plot the error as a function of n. If you just want a plausible value for n to get started, again, just use n = 3.
The second component is how to weight the contribution of each of the neighbors (assuming n > 1)....
Haskell Type vs Data Constructor
...ide what arguments they are going to put in.
A case study
As the home stretch here, we can consider the Maybe a type. Its definition is
data Maybe a = Nothing
| Just a
Here, Maybe is a type constructor that returns a concrete type. Just is a data constructor that returns a value. N...
Why does Python code run faster in a function?
... until a dictionary is requested (e.g. via locals(), or inspect.getframe() etc.). Looking up an array element by a constant integer is much faster than searching a dict.
– dmw
Jun 28 '12 at 21:53
...
Best explanation for languages without null
...azy null value that is meaningless to the graphing domain I'm working in. Etc.
When you do intend to model a possibly-non-existent value, then you should opt into it explicitly. If the way I intend to model people is that every Person has a FirstName and a LastName, but only some people have Midd...
What is private bytes, virtual bytes, working set?
...rfectly free to call VirtualAlloc, HeapAlloc (malloc and new in the CRTL), etc. It also tries to describe private memory size as a percentage of working set size, which is nonsensical. The former is a virtual size (and will be the same for every use of the code with the same input) while the latter ...
How do you parse and process HTML/XML in PHP?
... Javascript
Sort attributes, change character case, correct indentation, etc.
Extensible
Parsing documents using callbacks based on current character/token
Operations separated in smaller functions for easy overriding
Fast and Easy
Never used it. Can't tell if it's any ...
std::function vs template
... of the calculations of calc1 and calc2 are not the same, due to in-lining etc. Compare for example the sum of all results:
float result=0;
for (int i = 0; i < 1e8; ++i) {
result+=calc2([](float arg){ return arg * 0.5f; });
}
with calc2 that becomes
1.71799e+10, time spent 0.14 sec
while...
What does “dereferencing” a pointer mean?
...igher level libraries and applications, but code for OSes, device drivers, etc. may need to rely on behaviour left undefined by the C or C++ Standard, that is nevertheless well defined by their specific implementation or hardware.
...
What are the effects of exceptions on performance in Java?
... the exceptions themselves, the exact actions taken in exception handlers, etc.
The upshot is that when an exception isn't thrown, you don't pay a cost, so when the exceptional condition is sufficiently rare exception handling is faster than using an if every time. The full post is very much worth...
What are some compelling use cases for dependent method types?
...b: M) = 0;class CI extends C{type A=Int};class CS extends C{type A=String} etc.
– nafg
Oct 7 '13 at 23:26
...