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capturing self strongly in this block is likely to lead to a retain cycle
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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...
Regular Expression for alphanumeric and underscores
...o or more of the given characters
$ : end of string
If you don't want to allow empty strings, use + instead of *.
As others have pointed out, some regex languages have a shorthand form for [a-zA-Z0-9_]. In the .NET regex language, you can turn on ECMAScript behavior and use \w as a shorthand (y...
How to convert a Django QuerySet to a list
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Why not just call list() on the Queryset?
answers_list = list(answers)
This will also evaluate the QuerySet/run the query. You can then remove/add from that list.
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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...
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...
Passing a 2D array to a C++ function
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@Zack: You're right, there're only really two cases; one is a pointer-to-pointer and other being a single pointer to an integer array of size n i.e. int (*a) [10].
– legends2k
Jul 10 '13 at 10:44
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How to ignore user's time zone and force Date() use specific time zone
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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 ...
What are “named tuples” in Python?
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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...
mongodb/mongoose findMany - find all documents with IDs listed in array
I have an array of _ids and I want to get all docs accordingly, what's the best way to do it ?
5 Answers
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What does it mean if a Python object is “subscriptable” or not?
Which types of objects fall into the domain of "subscriptable"?
6 Answers
6
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