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How to initialize a private static const map in C++?
... int>’ as ‘this’ argument of ‘std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = int; _Tp = int; _Compare = std::less<int>; _Alloc = std::allocator<std::pair<const int, int>...
Does C have a “foreach” loop construct?
Almost all languages have a foreach loop or something similar. Does C have one? Can you post some example code?
12 Answer...
How to pretty-print a numpy.array without scientific notation and with given precision?
...335 0.712]
And suppress suppresses the use of scientific notation for small numbers:
y=np.array([1.5e-10,1.5,1500])
print(y)
# [ 1.500e-10 1.500e+00 1.500e+03]
np.set_printoptions(suppress=True)
print(y)
# [ 0. 1.5 1500. ]
See the docs for set_printoptions for other options.
T...
capturing self strongly in this block is likely to lead to a retain cycle
...
Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
What are “named tuples” in Python?
...
Named tuples are basically easy-to-create, lightweight object types. Named tuple instances can be referenced using object-like variable dereferencing or the standard tuple syntax. They can be used similarly to struct or other common record types...
How can I read SMS messages from the device programmatically in Android?
...ForResult(intent, 1);
}else {
List<Sms> lst = getAllSms();
}
}else {
List<Sms> lst = getAllSms();
}
Set app as default SMS app
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...languages or characters.
On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.
Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci
utf8mb4_unicode_ci, which uses the Unicode r...
Django Rest Framework: Dynamically return subset of fields
...verride the serializer __init__ method and set the fields attribute dynamically, based on the query params. You can access the request object throughout the context, passed to the serializer.
Here is a copy&paste from Django Rest Framework documentation example on the matter:
from rest_framew...
Output to the same line overwriting previous output?
...o need to import the sys module for this sort of simple usage. print() actually has a number of keyword arguments which can be used to greatly simplify code.
To use the same code on Python 2.6+, put the following line at the top of the file:
from __future__ import print_function
...
How to ignore user's time zone and force Date() use specific time zone
...
A Date object's underlying value is actually in UTC. To prove this, notice that if you type new Date(0) you'll see something like: Wed Dec 31 1969 16:00:00 GMT-0800 (PST). 0 is treated as 0 in GMT, but .toString() method shows the local time.
Big note, UTC stands ...