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Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
...t;> A + B
Counter({'c': 7, 'b': 5, 'd': 5, 'a': 1})
Counters are basically a subclass of dict, so you can still do everything else with them you'd normally do with that type, such as iterate over their keys and values.
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Multiple returns from a function
...
Technically, you can't return more than one value. However, there are multiple ways to work around that limitation. The way that acts most like returning multiple values, is with the list keyword:
function getXYZ()
{
return arr...
How to toggle a value in Python
...; toggle()
'blue'
Note that in Python 3 the next() method was changed to __next__(), so the first line would be now written as toggle = itertools.cycle(['red', 'green', 'blue']).__next__
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i...
Get an OutputStream into a String
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I would use a ByteArrayOutputStream. And on finish you can call:
new String( baos.toByteArray(), codepage );
or better:
baos.toString( codepage );
For the String constructor, the codepage can be a String or an instance of java.nio.charset.Charset. A possible value is java.nio.ch...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...
What's the difference between size_t and int in C++?
...ndly Wikipedia:
The stdlib.h and stddef.h header files define a datatype called size_t which is used to represent the size of an object. Library functions that take sizes expect them to be of type size_t, and the sizeof operator evaluates to size_t.
The actual type of size_t is platform-dependent; ...
Why Choose Struct Over Class?
...es in many circumstances.
Structs are preferable if they are relatively small and copiable because copying is way safer than having multiple references to the same instance as happens with classes. This is especially important when passing around a variable to many classes and/or in a multithreaded...
Get city name using geolocation
... as to which one will have the city.
"administrative_area_level_1" is usually what you are looking for but sometimes locality is the city you are after.
Anyhow - more details on google response types can be found here and here.
Below is the code that should do the trick:
<!DOCTYPE html> ...
std::unique_lock or std::lock_guard?
...er you need to relock the guard.
std::unique_lock has other features that allow it to e.g.: be constructed without locking the mutex immediately but to build the RAII wrapper (see here).
std::lock_guard also provides a convenient RAII wrapper, but cannot lock multiple mutexes safely. It can be us...