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What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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Count number of occurrences of a pattern in a file (even on same line)
When searching for number of occurrences of a string in a file, I generally use:
5 Answers
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How to create a file in a directory in java?
If I want to create a file in C:/a/b/test.txt , can I do something like:
11 Answers
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How to loop through an array containing objects and access their properties
I want to cycle through the objects contained in an array and change the properties of each one. If I do this:
15 Answers
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Does delete on a pointer to a subclass call the base class destructor?
I have an class A which uses a heap memory allocation for one of its fields. Class A is instantiated and stored as a pointer field in another class ( class B .
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What are some uses of template template parameters?
I've seen some examples of C++ using template template parameters (that is templates which take templates as parameters) to do policy-based class design. What other uses does this technique have?
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How to get client's IP address using JavaScript?
I need to somehow retrieve the client's IP address using JavaScript; no server side code, not even SSI.
50 Answers
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How to Reverse Fragment Animations on BackStack?
I thought the system would reverse animations on the backstack when the back button is pressed when using fragments using the following code:
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Get cookie by name
I have a getter to get the value from a cookie.
38 Answers
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How to run multiple shells on Emacs
I am using Emacs 23.3.1 on windows 7. I know that I can run shell from emacs using M-x shell. I would like to have multiple shell windows in the same time, but typing M-x shell a second time just opens me the same shell window.
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