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Pandas - How to flatten a hierarchical index in columns
I have a data frame with a hierarchical index in axis 1 (columns) (from a groupby.agg operation):
17 Answers
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Which way is best for creating an object in JavaScript? Is `var` necessary before an object property
... you happen to have all the properties you wish to set on hand at creation time.
For setting properties later, the NewObject.property1 syntax is generally preferable to NewObject['property1'] if you know the property name. But the latter is useful when you don't actually have the property's name a...
Python: most idiomatic way to convert None to empty string?
What is the most idiomatic way to do the following?
16 Answers
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Synchronization vs Lock
...d helps protect me from bugs in my code, but those same advantages are sometimes hindrances in more complex scenarios. Its these more complex scenarios that the concurrent package was created to help address. But using this higher level constructs requires more explicit and careful management in the...
Create objective-c class instance by name?
...or otherwise using a class that doesn't exist. You won't find out until runtime if you make that error. Instead, if you use the built-in objective-c type of Class to create a variable, then the compiler will verify that the class exists.
For example, in your .h:
@property Class NameOfClass;
and ...
How to fix the Hibernate “object references an unsaved transient instance - save the transient insta
...ules that don't allow all objects in a collection to get saved at the same time.
– Alex Marshall
Nov 19 '10 at 0:35
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How do I center align horizontal menu?
... The solution works great and I'm sorry to ask this after such a long time, but what if I have a css drop down? I can't use overflow:hidden in the parent then. But it'll still overflow like here: homeafrika.com .
– Samia Ruponti
Mar 28 '12 at 18:26
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How to find out which processes are using swap space in Linux?
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Same output ten times faster: for file in /proc/*/status ; do awk '/Tgid|VmSwap|Name/{printf $2 " " $3}END{ print ""}' $file; done | grep kB | sort -k 3 -n for Debian/RH 6x+, Arch, Ubuntu (RH 5x has VmSize) (source). Like @dgunchev it does ...
When should I use a struct instead of a class?
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I would use structs when:
an object is supposed to be read only(every time you pass/assign a struct it gets copied). Read only objects are great when it comes to multithreaded processing as they don't requite locking in most cases.
an object is small and short-living. In such a case there is a...
Can I find out the return value before returning while debugging in Visual Studio?
...our code, it's a one off debug and stepping through again will take a long time. (that's why I looked up this question anyway :-)
– Myster
Aug 16 '12 at 2:57
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