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What is the difference between “ is None ” and “ ==None ”
...mparison is implemented elementwise:
import numpy as np
a = np.zeros(3) # now a is array([0., 0., 0.])
a == None #compares elementwise, outputs array([False, False, False]), i.e. not boolean!!!
a is None #compares object to object, outputs False
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List all sequences in a Postgres db 8.1 with SQL
...ound in preferences to find a place to set it as default to no avail). Hm, now if only we had a "asker-accepted answer doesn't automatically trump everything else"-option, that would be a truly great victory for posterity.
– SeldomNeedy
Jul 28 '15 at 16:52
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Pass correct “this” context to setTimeout callback?
...ause it wasn't yet widely supported and you needed polyfills to use it but now it's everywhere:
if (this.options.destroyOnHide) {
setTimeout(function(){ this.tip.destroy() }.bind(this), 1000);
}
The bind function creates a new function with the this value pre-filled.
Now in modern JS, this ...
How can you disable Git integration in Visual Studio 2013 permanently?
I know that you can disable git integration by using the Tools / Options dialog, but what I've noticed is that this setting doesn't seem to persist across sessions; i.e., as soon as close and reopen the solution, Git integration is enabled again. I'm guessing Visual Studio is seeing the .git folder ...
How can I reliably get an object's address when operator& is overloaded?
...regular member functions of a template class, thanks for pointing it out. (Now I just need to figure out what is the use of the overload, any tip ?)
– Matthieu M.
Jun 27 '11 at 16:50
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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
..._id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACTION
Now simply issue an:
alter table region drop foreign key
region_ibfk_1;
And finally an:
alter table region drop column
country_id;
And you are good to go!
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What's the difference between lists and tuples?
... the first box under 3. Permitted operation shows the tuple case first. I know it is usual to show success then error, but that messed with my head for a few moments.
– dmckee --- ex-moderator kitten
Sep 10 '18 at 15:08
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What is the most efficient way to deep clone an object in JavaScript?
...ined properties, etc., but this will also slow you down a little.
If you know the structure of the objects you are trying to clone or can avoid deep nested arrays you can write a simple for (var i in obj) loop to clone your object while checking hasOwnProperty and it will be much much faster than j...
Failed to install Python Cryptography package with PIP and setup.py
...:
sudo yum install gcc libffi-devel python-devel OpenSSL-devel
You should now be able to build and install cryptography with the usual.
pip install cryptography
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Suppressing “warning CS4014: Because this call is not awaited, execution of the current method conti
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With C# 7 you can now use discards:
_ = WorkAsync();
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