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What's the fastest way to merge/join data.frames in R?
...version.string
# R version 2.15.1 (2012-06-22)
Please note that I don't know plyr well so please do check with Hadley before relying on the plyr timings here. Also note that the data.table do include the time to convert to data.table and set the key, for fareness.
This answer has been updated s...
How does this print “hello world”?
...g the number with the mask 31₁₀ = 11111₂ in the sentence l & 31
Now the code maps the 5-bit value to its corresponding 7-bit ascii character. This is the tricky part, check the binary representations for the lowercase
alphabet letters in the following table:
ascii | ascii | ...
Read/write to Windows registry using Java
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I know this question is old, but it is the first search result on google to "java read/write to registry". Recently I found this amazing piece of code which:
Can read/write to ANY part of the registry.
DOES NOT USE JNI.
DOES...
In PHP, what is a closure and why does it use the “use” identifier?
... So it's ONLY used for closures? Thanks for you explanation, I did not know the difference between anonymous function and a closure
– SeanDowney
Jun 30 '09 at 19:01
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What is the exact problem with multiple inheritance?
...s say have two classes A and B, both of which define a method doSomething. Now you define a third class C, which inherits from both A and B, but you don't override the doSomething method.
When the compiler seed this code...
C c = new C();
c.doSomething();
...which implementation of the method sh...
What is the difference between a strongly typed language and a statically typed language?
... CLU, F#, and Haskell it is yes. For C++ I am not sure—I would like to know.
By contrast, static typing means that programs are checked before being executed, and a program might be rejected before it starts. Dynamic typing means that the types of values are checked during execution, and a poo...
How to solve error “Missing `secret_key_base` for 'production' environment” (Rails 4.1)
... But, i has no effect, when I restarting Unicorn. The only way, that works now, is pasting it directly to secrets.yml
– AntonAL
Nov 17 '14 at 20:37
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Static files in Flask - robot.txt, sitemap.xml (mod_wsgi)
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Heads up - there's an easier way to handle this now. Check my reply.
– Sean McSomething
Jan 17 '13 at 23:00
1
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Horizontal ListView in Android?
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It is deprectaed now
– Animesh Mangla
Dec 27 '15 at 13:05
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Implementing Comments and Likes in database
...be changed without affecting any code: only the stored procedures should know about the schema.
You may have to refactor the schema several times. This is normal. Don't worry about getting it perfect the first time. Just make it functional enough to prototype an initial design. If you have the...