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Scala list concatenation, ::: vs ++
Is there any difference between ::: and ++ for concatenating lists in Scala?
4 Answers
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How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
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What's the best way to join on the same table twice?
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First, I would try and refactor these tables to get away from using phone numbers as natural keys. I am not a fan of natural keys and this is a great example why. Natural keys, especially things like phone numbers, can change and frequently so....
Efficient way to apply multiple filters to pandas DataFrame or Series
I have a scenario where a user wants to apply several filters to a Pandas DataFrame or Series object. Essentially, I want to efficiently chain a bunch of filtering (comparison operations) together that are specified at run-time by the user.
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Difference between numpy.array shape (R, 1) and (R,)
...ning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data buffer which is just a block...
Google Maps V3 - How to calculate the zoom level for a given bounds
...e willing to change the size of the map div, you have to choose which size and corresponding zoom level you change to (roughly speaking, do you make it larger or smaller than it currently is?).
If you really need to calculate the zoom, rather than store it, this should do the trick:
The Mercator p...
Use C++ with Cocoa Instead of Objective-C?
I would like to write applications that use C++ and the Cocoa frameworks because Apple is not making Carbon 64-bit capable. C++ seems to be pretty vanilla in its implementation on Linux and Windows but on Mac OS X it seems like additional Apple specific pieces of code are required (like an Obj-C wra...
More elegant way of declaring multiple variables at the same time
...called function. This is certainly a reliable way to create dictionaries, and people seem to be at least accepting of this idiom, but I suspect that some may consider it Unpythonic. </disclaimer>
Yet another approach, which is likely the most intuitive if you will be using this pattern fr...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
... a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the.lock
[Terminal #2] lockfile: Sorry, giving up on "/tmp/the.lock"
[Terminal #1] $ rm -f /tmp/the....
How to print a query string with parameter values when using Hibernate
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I am using grails 2.4.4 and hibernate 4. Changing log4j configuration did not work for me but p6spy worked!
– Champ
Jan 13 '15 at 7:03
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