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Extracting numbers from vectors of strings
...ion is an indirect way of getting to the solution. If you want to retrieve all the numbers, I recommend gregexpr:
matches <- regmatches(years, gregexpr("[[:digit:]]+", years))
as.numeric(unlist(matches))
If you have multiple matches in a string, this will get all of them. If you're only intere...
Why does `a == b or c or d` always evaluate to True?
...r is more literal minded.
if name == "Kevin" or "Jon" or "Inbar":
is logically equivalent to:
if (name == "Kevin") or ("Jon") or ("Inbar"):
Which, for user Bob, is equivalent to:
if (False) or ("Jon") or ("Inbar"):
The or operator chooses the first argument with a positive truth value:
if ("Jon")...
Java SE 6 vs. JRE 1.6 vs. JDK 1.6 - What do these mean?
I see many different Java terms floating around. I need to install the JDK 1.6. It was my understanding that Java 6 == Java 1.6. However, when I install Java SE 6, I get a JVM that reports as version 11.0! Who can solve the madness?
...
How do I perform a Perl substitution on a string while keeping the original?
...
I was wondering if something like my $new = $_ for $old =~ s/foo/bar; would work?
– Benoit
Apr 30 '14 at 17:11
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ASP.NET MVC: Is Controller created for every request?
...ther controller.
The short version is that ControllerActivator.Create is called (for every request) to create a Controller (which inits a new Controller either through the DependencyResolver or through the Activator if no Resolver has been set up):
public IController Create(RequestContext requestC...
Align image in center and middle within div
...00%; height:100%">
<img src="http://www.garcard.com/images/garcard_symbol.png">
</div>
JSFiddle
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Make a UIButton programmatically in Swift
..., 500)
myFirstButton.addTarget(self, action: #selector(myClass.pressed(_:)), forControlEvents: .TouchUpInside)
self.view.addSubview(myFirstLabel)
self.view.addSubview(myFirstButton)
}
@objc func pressed(sender: UIButton!) {
var alertView = UIAlertView()
alertView.addButtonWithTi...
Equation (expression) parser with precedence?
...ursively, for example, using your sample string,
1+11*5
to do this manually, you would have to read the 1, then see the plus and start a whole new recursive parse "session" starting with 11... and make sure to parse the 11 * 5 into its own factor, yielding a parse tree with 1 + (11 * 5).
This a...
How can I remove all my changes in my SVN working directory?
...ctory, and it shows in svn status . But is there any way for me to remove all my changes in there and just get everything from the trunk using the command line?
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AngularJS error: 'argument 'FirstCtrl' is not a function, got undefined'
...nswered Oct 16 '13 at 15:54
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