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How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
How do I open links in Visual Studio in my web browser and not in Visual Studio?
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There is an extension that provides this behavior called Open in External Browser. It works in Visual Studio 2012, 2013, 2015 and 2017. (An old version available on GitHub supports Visual Studio 2010.)
Thanks goes to Dmitry for pointing this out in his answer to this similar...
Using AES encryption in C#
...aged.aspx
And just in case you need the sample in a hurry, here it is in all its plagiarized glory:
using System;
using System.IO;
using System.Security.Cryptography;
namespace RijndaelManaged_Example
{
class RijndaelExample
{
public static void Main()
{
try
...
java.net.URLEncoder.encode(String) is deprecated, what should I use instead?
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He's calling it bloated because its overpopulating the global class namespace. Why have URLEncoder.encode and URLDecoder.decode when you could have URL.encode and URL.decode, or even just URLEncoder.decode? Why make it all redundan...
Difference between -pthread and -lpthread while compiling
...that get defined when the -pthread option gets used on the GCC package installed on my Ubuntu machine:
$ gcc -pthread -E -dM test.c > dm.pthread.txt
$ gcc -E -dM test.c > dm.nopthread.txt
$ diff dm.pthread.txt dm.nopthread.txt
152d151
< #define _REENTRANT 1
208d206
< #define _...
Split Python Flask app into multiple files
...like this:
Main.py
from flask import Flask
from AccountAPI import account_api
app = Flask(__name__)
app.register_blueprint(account_api)
@app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run()
AccountAPI.py
from flask import Blueprint
account_api = Bl...
How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
I've a timer object. I want it to be run every minute. Specifically, it should run a OnCallBack method and gets inactive while a OnCallBack method is running. Once a OnCallBack method finishes, it (a OnCallBack ) restarts a timer.
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Python function attributes - uses and abuses [closed]
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I typically use function attributes as storage for annotations. Suppose I want to write, in the style of C# (indicating that a certain method should be part of the web service interface)
class Foo(WebService):
@webmethod
de...