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Can dplyr package be used for conditional mutating?
...s it can evaluate both 'yes' and 'no' cases, and nesting can get harder to read/maintain IMHO.
Here's a benchmark on relatively bigger data:
# R version 3.1.0
require(data.table) ## 1.9.2
require(dplyr)
DT <- setDT(lapply(1:6, function(x) sample(7, 1e7, TRUE)))
setnames(DT, letters[1:6])
# &...
How many threads is too many?
I am writing a server, and I send each action of into a separate thread when the request is received. I do this because almost every request makes a database query. I am using a threadpool library to cut down on construction/destruction of threads.
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How can I save my secret keys and password securely in my version control system?
...box or whoever is storing your files under VC does not have the ability to read the information in plaintext.
Tutorial on Transparent Encryption/Decryption during Push/Pull
This gist https://gist.github.com/873637 shows a tutorial on how to use the Git's smudge/clean filter driver with openssl to ...
Where to use EJB 3.1 and CDI?
...g to align them. What aligning means is allowing people to do what they already can do, just without the @Stateful, @Stateless or @Singleton annotation at the top.
EJB and CDI in Implementation Terms
Ultimately, EJB and CDI share the same fundamental design of being proxied components. When you ...
CSRF Token necessary when using Stateless(= Sessionless) Authentication?
... token auth?
JWT (Json Web Token): I think it's still a draft, but it's already used by many people and the concept looks simple and secure. (IETF: http://tools.ietf.org/html/draft-ietf-oauth-json-web-token-25 )
There are also libraries for lot's of framework available. Just google for it!
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Constructor function vs Factory functions
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As you already mentioned that some people try to use factory functions just because they don't intend to leave bugs where people forget to use new with the constructor function; I thought it's where one might need to see a how to repl...
When should I use the Visitor Design Pattern? [closed]
...he visitor pattern in blogs but I've got to admit, I just don't get it. I read the wikipedia article for the pattern and I understand its mechanics but I'm still confused as to when I'd use it.
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Use RSA private key to generate public key?
...H-KEYGEN(1)
ssh-keygen -y [-f input_keyfile]
-y This option will read a private OpenSSH format file and print an OpenSSH public key to stdout.
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Callback functions in C++
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A function pointer is the 'simplest' (in terms of generality; in terms of readability arguably the worst) type a callback can have.
Let's have a simple function foo:
int foo (int x) { return 2+x; }
1.1 Writing a function pointer / type notation
A function pointer type has the notation
return...
How do I execute code AFTER a form has loaded?
...or me, in C#. I had to add Shown += Form1_Shown; as suggested in another thread
– ocramot
May 18 '15 at 8:17
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