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How to determine a Python variable's type?
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answered Dec 31 '08 at 10:43
gregjorgregjor
16.7k11 gold badge1818 silver badges1414 bronze badges
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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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Do zombies exist … in .NET?
I was having a discussion with a teammate about locking in .NET. He's a really bright guy with an extensive background in both lower-level and higher-level programming, but his experience with lower level programming far exceeds mine. Anyway, He argued that .NET locking should be avoided on critic...
What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...
Sequelize.js delete query?
Is there a way to write a delete/deleteAll query like findAll?
9 Answers
9
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How to get the directory of the currently running file?
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It actually works even if os.Args[0] does not contain the abs path. The reason the playground result is not what you expected is because it is inside a sandbox.
– Gustavo Niemeyer
Jul 21 '15 at...
What is the difference between sigaction and signal?
...ion() avoids - unless you use the flags explicitly added to sigaction() to allow it to faithfully simulate the old signal() behaviour.
The signal() function does not (necessarily) block other signals from arriving while the current handler is executing; sigaction() can block other signals until the...
When should you not use virtual destructors?
...o not declare a virtual destructor for a class? When should you specifically avoid writing one?
12 Answers
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How do I convert Word files to PDF programmatically? [closed]
I have found several open-source/freeware programs that allow you to convert .doc files to .pdf files, but they're all of the application/printer driver variety, with no SDK attached.
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Symfony 2: How do I check if a user is not logged in inside a template?
...any user is logged in.
{% if app.user %}
# user is logged in (any and all users, regardless of ROLE_*)
{% elseif not app.user %}
# user is not logged in (note the `not` in the `elseif` statement)
{% endif %}
Checking authentication status
You can use the is_granted() method to check fo...