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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...t.org/doc/manuals/R-lang.html#Indexing
R has three basic indexing operators, with syntax displayed by the following examples
x[i]
x[i, j]
x[[i]]
x[[i, j]]
x$a
x$"a"
For vectors and matrices the [[ forms are rarely used, although they have some slight semantic differen...
Convert Pixels to Points
I have a need to convert Pixels to Points in C#. I've seen some complicated explanations about the topic, but can't seem to locate a simple formula. Let's assume a standard 96dpi, how do I calulate this conversion?
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How to sort a list/tuple of lists/tuples by the element at a given index?
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Any idea how to sort it bigger to smaller?
– billwild
Dec 19 '12 at 13:57
65
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Change Author template in Android Studio
I want to change the automatic author that appears when I create a file in AndroidStudio.
7 Answers
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How can I add an item to a SelectList in ASP.net MVC
Basically I am looking to insert an item at the beginning of a SelectList with the default value of 0 and the Text Value of " -- Select One --"
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What is an anti-pattern?
...are development that are considered bad programming practices.
As opposed to design patterns which are common approaches to common problems which have been formalized and are generally considered a good development practice, anti-patterns are the opposite and are undesirable.
For example, in objec...
Google Maps: How to create a custom InfoWindow?
...oogle Maps InfoWindow for a map marker is very round. How do I create a custom InfoWindow with square corners?
10 Answers
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How do I check if a file exists in Java?
...le:
File f = new File(filePathString);
if(f.exists() && !f.isDirectory()) {
// do something
}
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Difference between as.POSIXct/as.POSIXlt and strptime for converting character vectors to POSIXct/PO
I have followed a number of questions here that asks about how to convert character vectors to datetime classes. I often see 2 methods, the strptime and the as.POSIXct/as.POSIXlt methods. I looked at the 2 functions but am unclear what the difference is.
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How to explore web-based Google Play in another country?
if I go to play.google.com, it automatically recognizes my country and allow me to browse the apps for that country. I can change the language through the dropdown in the footer, or I can add &hl=code in the querystring...but that only changes the language...not the store content (the app lists and ...