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Replace a value in a data frame based on a conditional (`if`) statement
...
that doesn't work on the data as created by @Kenny because the data are factors. Did you forget a step or do you have the global setting to stop converting characters to factors?
– Gavin Simpson
Apr 28 '11 at 20:27
...
How to generate an openSSL key using a passphrase from the command line?
...out pass:foobar 3072
However, note that this passphrase could be grabbed by any other process running on the machine at the time, since command-line arguments are generally visible to all processes.
A better alternative is to write the passphrase into a temporary file that is protected with file ...
What does the `#` operator mean in Scala?
...hich means a B nested class of any instance of A.
We can see this in work by changing the code above:
class A {
class B
def f(b: B) = println("Got my B!")
def g(b: A#B) = println("Got a B.")
}
And trying it out:
scala> val a1 = new A
a1: A = A@1497b7b1
scala> val a2 = new A
a2: A ...
What's the difference between “Request Payload” vs “Form Data” as seen in Chrome dev tools Network t
...e more precise: payload body of a HTTP Request
- is the data normally send by a POST or PUT Request.
It's the part after the headers and the CRLF of a HTTP Request.
A request with Content-Type: application/json may look like this:
POST /some-path HTTP/1.1
Content-Type: application/json
{ "foo" : ...
Prevent browser caching of AJAX call result
... downvote only because it's cleaner to let jQuery do this as in the answer by Peter J. Your solution will work, but is more difficult to maintain in the long run.
– Niklas Wulff
Jan 13 '11 at 12:46
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How to debug .htaccess RewriteRule not working
...to your .htaccess
e.g. foo bar, sakjnaskljdnas
any keyword not recognized by htaccess
and visit your URL. If it is working, you should get a
500 Internal Server Error
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your re...
Using IoC for Unit Testing
... in a huge solution (50+ projects) using IoC?
I'm not sure what you mean by managing mocks using IoC. Anyway, IoC containers can usually do more than just injecting mocks when it comes to testing. And if you have decent IDE support that makes refactoring possible, why not using it?
Any experie...
What is the difference between Lisp-1 and Lisp-2?
...
You might like to read this paper by Richard Gabriel. It is a summary of the issues that the Lisp community were discussing in Lisp1 vs Lisp2. It's a bit dense and slow moving in the first few sections, but is much easier to read by the time you get past sec...
Async/Await vs Threads
...a transfer it generates a completion notification callback. Networking is by far the most common usage, latencies of hundreds of milliseconds are common and an inevitable side-effect of services moving from the desktop or a LAN into "the cloud". Using such services synchronously would make a UI qu...
What's the best way to communicate between view controllers?
...ey need to work with. Most changes are communicated back up the hierarchy by using NSNotificationCenter; firing the notifications is usually built in to the model itself.
For example, suppose I have an app with Accounts and Transactions. I also have an AccountListController, an AccountController ...