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How do you get the index of the current iteration of a foreach loop?
...or iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator.
This Enumerator has a method and a property:
MoveNext()
Current
Current returns the object that Enumerator is currently on, MoveNext updates Current t...
Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
...
MySQL: #126 - Incorrect key file for table
... a ramdisk configured. You can temporarily comment out the ramdisk line to allow such operations if you can't increase the size of it.
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LINQ equivalent of foreach for IEnumerable
...Multi-threading, possible by PLINQ. 2. Exceptions, you may want to collect all exception in the loop and throw it at once; and they are noise codes.
– Dennis C
Feb 7 '10 at 7:06
13...
Globally override key binding in Emacs
How can I set a key binding that globally overrides and takes precedence over all other bindings for that key? I want to override all major/minor mode maps and make sure my binding is always in effect.
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Is there an equivalent for var_dump (PHP) in Javascript?
...vidual property: some objects have a LOT of properties and you'll be there all day clicking "OK", "OK", "OK", "O... dammit that was the property I was looking for".
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C# 通过代码安装、卸载、启动、停止服务 - .NET(C#) - 清泛IT论坛，有思想、有深度
...sp; IDictionary _SavedState = new Hashtable();
ServiceController service = new ServiceController(serviceName);
 ...
Using querySelectorAll to retrieve direct children
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Good question. At the time it was asked, a universally-implemented way to do "combinator rooted queries" (as John Resig called them) did not exist.
Now the :scope pseudo-class has been introduced. It is not supported on [pre-Chrominum] versions of Edge or IE, but has been s...
Loaded nib but the 'view' outlet was not set
...s are right, but as I'm a newcomer it took me a little while to figure out all the steps to do that. Here's what worked for me:
Open the XIB file causing problems
Click on file's owner icon on the left bar (top one, looks like a yellow outlined box)
If you don't see the right-hand sidebar, click o...