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Why does an overridden function in the derived class hide other overloads of the base class?
...happens, people who respond either say that this called "name hiding" and em>x m>plain how it works (which you probably already know), or em>x m>plain how to override it (which you never asked about), but nobody seems to care to address the actual "why" question.
The decision, the rationale behind the name h...
Are lists thread-safe?
...y attempts to concurrently access, the lists's data is not protected. For em>x m>ample:
L[0] += 1
is not guaranteed to actually increase L[0] by one if another thread does the same thing, because += is not an atomic operation. (Very, very few operations in Python are actually atomic, because most of t...
PostgreSQL array_agg order
...g the input values from a sorted subquery will usually work, however. For em>x m>ample:
SELECT m>x m>mlagg(m>x m>) FROM (SELECT m>x m> FROM test ORDER BY y DESC) AS tab;
So in your case you would write:
SELECT
array_to_string(array_agg(animal_name),';') animal_names,
array_to_string(array_agg(animal_type),';') ...
Why does (1 in [1,0] == True) evaluate to False?
...
Python actually applies comparison operator chaining here. The em>x m>pression is translated to
(1 in [1, 0]) and ([1, 0] == True)
which is obviously False.
This also happens for em>x m>pressions like
a < b < c
which translate to
(a < b) and (b < c)
(without evaluating b twice...
How to convert latitude or longitude to meters?
...), Math.sqrt(1-a));
var d = R * c;
return d * 1000; // meters
}
Em>x m>planation: https://en.wikipedia.org/wiki/Haversine_formula
The haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes.
...
What JSON library to use in Scala? [closed]
...json.JSON - Warning this library is available only up to Scala version 2.9.m>x m> (removed in newer versions)
spray-json - Em>x m>tracted from the Spray project
Jerkson ± - Warning a nice library (built on top of Java Jackson) but now abandonware. If you are going to use this, probably follow the Scalding pr...
D3.js: what is 'g' in .append(“g”) D3.js code?
...t always enlightens: developer.mozilla.org/en/docs/Web/SVG/Element/g. An em>x m>perimental pen can be found here: codepen.io/ahujamoh/pen/brRpWM
– Mohit
Aug 10 '17 at 12:14
add a ...
Understanding em>x m>actly when a data.table is a reference to (vs a copy of) another data.table
...Some operations seem to 'break' the reference, and I'd like to understand em>x m>actly what's happening.
2 Answers
...
How do I typedef a function pointer with the C++11 using syntam>x m>?
...
It has a similar syntam>x m>, em>x m>cept you remove the identifier from the pointer:
using FunctionPtr = void (*)();
Here is an Em>x m>ample
If you want to "take away the uglyness", try what m>X m>eo suggested:
#include <type_traits>
using FunctionPtr = ...
Why does Math.floor return a double?
...l to the argument and is equal to a mathematical integer". Given a value m>x m> > 2^53 that will not be the same as the value with its fractional part truncated. It may well be quite a bit smaller than that.
– Jim Garrison
Sep 5 '16 at 20:10
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