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Any reason not to use '+' to concatenate two strings?
... Tuple would be faster - the code was just an example :) Usually long multiple string inputs are dynamic.
– Mikko Ohtamaa
Apr 6 '12 at 12:52
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Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
HTML input file selection event not firing upon selecting the same file
... is prefixed with 'C:\fakepath\'. That's a security feature preventing JavaScript from knowing the file's absolute path. The browser still knows it internally.
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Is the C# static constructor thread safe?
... {
mutex.WaitOne();
return instance;
}
// Each call to Acquire() requires a call to Release()
public static void Release()
{
mutex.ReleaseMutex();
}
}
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What's a correct and good way to implement __hash__()?
...be integers, and there aren't too many of them, I suppose you could potentially run slightly faster with some home-rolled hash, but it likely wouldn't be as well distributed. hash((self.attr_a, self.attr_b, self.attr_c)) is going to be surprisingly fast (and correct), as creation of small tuples is ...
How to edit a node module installed via npm?
...the local system, but the change does not seem to affect. Changing any javascript file which is node_modules/package_name/lib/file_name.js does affect?
– inquisitive
Apr 16 '15 at 13:04
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Django 1.7 - makemigrations not detecting changes
... may happen due to the following reasons:
You did not add the app in INSTALLED_APPS list in settings.py
(You have to add either the app name or the dotted path to the subclass of AppConfig in apps.py in the app folder, depending on the version of django you are using). Refer documentation: INST...
How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
How do I check if a variable exists in a list in BASH
I am trying to write a script in bash that check the validity of a user input.
I want to match the input (say variable x ) to a list of valid values.
...
open read and close a file in 1 line of code
...
You don't really have to close it - Python will do it automatically either during garbage collection or at program exit. But as @delnan noted, it's better practice to explicitly close it for various reasons.
So, what you can do to keep ...