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How to append rows to an R data frame
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Not knowing what you are trying to do, I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, def...
Why is `std::move` named `std::move`?
The C++11 std::move(x) function doesn't really move anything at all. It is just a cast to r-value. Why was this done? Isn't this misleading?
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How can I pass command-line arguments to a Perl program?
...rbose); # flag
Alternatively, @ARGV is a special variable that contains all the command line arguments. $ARGV[0] is the first (ie. "string1" in your case) and $ARGV[1] is the second argument. You don't need a special module to access @ARGV.
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“Wrap with try…catch” in IntelliJ?
...ity Guide under the Help menu from time to time. Not only does it tell me all the shortcuts, but it keeps track of how many times I've used each one and when I last used it. I can see how well I'm leveraging the shortcuts.
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How to make IPython notebook matplotlib plot inline
...rt numpy as np
import matplotlib.pyplot as plt
You can also always start all your IPython kernels in inline mode by default by setting the following config options in your config files:
c.IPKernelApp.matplotlib=<CaselessStrEnum>
Default: None
Choices: ['auto', 'gtk', 'gtk3', 'inline', '...
Keep-alive header clarification
... is recognized by source IP and port and destination IP and port. Your OS, all intermediate session-aware devices and the server's OS will recognize the connection by this.
HTTP works with request-response: client connects to server, performs a request and gets a response. Without keep-alive, the c...
What is Angular.noop used for?
...laceholder when you need to pass some function as a param.
function foo (callback) {
// Do a lot of complex things
callback();
}
// Those two have the same effect, but the later is more elegant
foo(function() {});
foo(angular.noop);
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html5 localStorage error with Safari: “QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to
...wsing mode, it appears as though localStorage is available, but trying to call setItem throws an exception.
store.js line 73
"QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to add something to storage that exceeded the quota."
What happens is that the window object still exposes localS...
Efficiency of purely functional programming
...ssible asymptotic slowdown that can happen when programming purely functionally as opposed to imperatively (i.e. allowing side-effects)?
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Do asynchronous operations in ASP.NET MVC use a thread from ThreadPool on .NET 4
...hronous processing in ASP.NET (which is what asynchronous controllers basically represent).
Let's first consider a standard synchronous action:
public ActionResult Index()
{
// some processing
return View();
}
When a request is made to this action a thread is drawn from the thread pool a...