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Pandas - How to flatten a hierarchical index in columns
..., but leaves behind column names which are difficult to access programmatically and are not queriable
– dmeu
Jun 29 '17 at 8:53
1
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Case insensitive searching in Oracle
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Since 10gR2, Oracle allows to fine-tune the behaviour of string comparisons by setting the NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', ...
Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...
Are list-comprehensions and functional functions faster than “for loops”?
...ike map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?.
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Ignore .pyc files in git repository
...t to to do it beforehand, if you just add the line to the .gitignore file, all previously committed .pyc files will still be tracked, so you'll need to remove them from the repository.
If you are on a Linux system (or "parents&sons" like a MacOSX), you can quickly do it with just this one line ...
ASP.NET Identity's default Password Hasher - How does it work and is it secure?
...ff using decimal numbers is A LOT more intuitive (we have 10 fingers after all - at least most of us), so declaring a number of something using hexadecimals seems like an unnecessary code obfuscation.
– Andrew Cyrul
Apr 13 '17 at 9:27
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rgdal package installation
...liam Kyngesburye at http://www.kyngchaos.com/ may be used for
source installs on OSX.
As you seem to be under Linux, you always build package from source, so you will have to install the corresponding libraries on your system. If you are under Mint, Ubuntu or another Debian derivative, you can d...
Does Swift support reflection?
...s to me it's just a hack to enable debugging in Xcode. Protocol Mirror actually quotes the word IDE several times.
– Sulthan
Jun 6 '14 at 7:50
7
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Failed to load the JNI shared Library (JDK)
...) being loaded into an application. Now imagine a 32bit function wants to call a 64bit one, or alike. Same with alignment and datasizes and everything. I guess I dont have to tell anything more =P
– imacake
Mar 17 '12 at 17:15
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What is “:-!!” in C code?
...sizeof(struct { int: -!!(e); }))
(e): Compute expression e.
!!(e): Logically negate twice: 0 if e == 0; otherwise 1.
-!!(e): Numerically negate the expression from step 2: 0 if it was 0; otherwise -1.
struct{int: -!!(0);} --> struct{int: 0;}: If it was zero, then we declare a struct with an an...