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Checking if a double (or float) is NaN in C++
...nly if f is NaN.
Note that, as some comments below have pointed out, not all compilers respect this when optimizing code.
For any compiler which claims to use IEEE floating point, this trick should work. But I can't guarantee that it will work in practice. Check with your compiler, if in doubt.
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Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
Select random lines from a file
... @MonaJalal nope just faster, since it doesn't have to compare lines at all.
– rogerdpack
May 15 '17 at 17:20
Does ...
In-place type conversion of a NumPy array
...Py array of int32 , how do I convert it to float32 in place ? So basically, I would like to do
6 Answers
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Getting an empty JQuery object
...tion about it, but I solved it by using PHP instead of jQuery so I can't really dig more into it right now.
– cregox
Mar 2 '11 at 19:02
2
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Overriding superclass property with different type in Swift
...
Swift does not allow you to change the class type of any variables or properties. Instead you can create an extra variable in the subclass that handles the new class type:
class Chassis {}
class RacingChassis : Chassis {}
class Car {
...
Multiple “order by” in LINQ
...
How on earth have I gone all this time without knowing about ThenBy?! (Edit: looks like it was introduced in .NET 4.0, which explains how it slipped past me unnoticed.)
– Jordan Gray
Nov 21 '13 at 15:05
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What's the difference between a file descriptor and file pointer?
...ther Unix-like systems.
You pass "naked" file descriptors to actual Unix calls, such as read(), write() and so on.
A FILE pointer is a C standard library-level construct, used to represent a file. The FILE wraps the file descriptor, and adds buffering and other features to make I/O easier.
You pa...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
Convert a python 'type' object to a string
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...