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Dynamically set local variable [duplicate]
How do you dynamically set local variable in Python (where the variable name is dynamic)?
7 Answers
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Getting MAC Address
... says that it will return a random long if it fails to detect the mac: "If all attempts to obtain the hardware address fail, we choose a random 48-bit number with its eighth bit set to 1 as recommended in RFC 4122." So check that eighth bit!
– deinonychusaur
Fe...
How to install therubyracer gem on 10.10 Yosemite?
I don't manage to install therubyracer gem on Yosemite 10.10.
18 Answers
18
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print call stack in C or C++
Is there any way to dump the call stack in a running process in C or C++ every time a certain function is called? What I have in mind is something like this:
...
How do I search for an object by its ObjectId in the mongo console?
...
Not strange at all, people do this all the time. Make sure the collection name is correct (case matters) and that the ObjectId is exact.
Documentation is here
> db.test.insert({x: 1})
> db.test.find() ...
PHP $_SERVER['HTTP_HOST'] vs. $_SERVER['SERVER_NAME'], am I understanding the man pages correctly?
...you either go with that or you check the host name against a white list:
$allowed_hosts = array('foo.example.com', 'bar.example.com');
if (!isset($_SERVER['HTTP_HOST']) || !in_array($_SERVER['HTTP_HOST'], $allowed_hosts)) {
header($_SERVER['SERVER_PROTOCOL'].' 400 Bad Request');
exit;
}
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What does “dereferencing” a pointer mean?
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Reviewing the basic terminology
It's usually good enough - unless you're programming assembly - to envisage a pointer containing a numeric memory address, with 1 referring to the second byte in the process's memory, 2 the third, 3 the fourth and so on....
What ha...
Null coalescing in powershell
...t the Powershell versions involving functions/aliases will always evaluate all arguments. If this is a problem, use the if expression form.
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Abstract methods in Python [duplicate]
...what a metaclass is, don't worry about it. :-)
– kindall
Dec 8 '10 at 0:15
1
The linked tutorial ...
Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
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