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Run R script from command line
...ou really want to use the ./a.R way of calling the script you could add an appropriate #! to the top of the script
#!/usr/bin/env Rscript
sayHello <- function(){
print('hello')
}
sayHello()
I will also note that if you're running on a *unix system there is the useful littler package which ...
Why are regular expressions so controversial? [closed]
...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs.
– Pacerier
Dec 1 '15 at 21:53
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IntelliJ IDEA with Junit 4.7 “!!! JUnit version 3.8 or later expected:”
...
This problem happens because Android Platform (android.jar) already contains JUnit classes. IDEA test runner loads these classes and sees that they are from the old JUnit, while you are trying to use annotated tests which is a feature of t...
Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy
...iewDidLoad method. The solution for me was to move this call to the viewDidAppear: method.
My presumption is that the view controller's view is not in the window's view hierarchy at the point that it has been loaded (when the viewDidLoad message is sent), but it is in the window hierarchy after it ...
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...
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?
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Value cannot be null. Parameter name: source
...;
</defaultConnectionFactory>
</entityFramework>
What's happening is that it's looking for a data source in the wrong place; Entity Framework specifies it slightly differently. If you post your connection string and EF config then we can check.
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Java: int array initializes with nonzero elements
...here it is not. Such a behavior occurs first in JDK 7u4 and also occurs in all later updates (I use 64-bit implementation). The following code throws exception:
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What's the best way to build a string of delimited items in Java?
While working in a Java app, I recently needed to assemble a comma-delimited list of values to pass to another web service without knowing how many elements there would be in advance. The best I could come up with off the top of my head was something like this:
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Trigger a button click with JavaScript on the Enter key in a text box
... This worked for me due to fact that the inline method, instead of calling function with similar code in it, allows you to return false on the call and avoid postback. In my case the "click" method invokes a __doPostback async call and without the "return false;" would just reload the page.
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