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How to append rows to an R data frame

...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame. Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as: # pre-allocate space f3 <- function(n){ df <- data.frame(x = numeric(n)...
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JavaScript curry: what are the practical applications?

I don’t think I’ve grokked currying yet. I understand what it does, and how to do it. I just can’t think of a situation I would use it. ...
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Display date/time in user's locale format and time offset

I want the server to always serve dates in UTC in the HTML, and have JavaScript on the client site convert it to the user's local timezone. ...
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List comprehension vs. lambda + filter

I happened to find myself having a basic filtering need: I have a list and I have to filter it by an attribute of the items. ...
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history.replaceState() example?

...ough intentional for 2 years now. The problem lies with some unclear specs and the complexity when document.title and back/forward are involved. See bug reference on Webkit and Mozilla. Also Opera on the introduction of History API said it wasn't using the title parameter and probably still doesn't...
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Understanding Fragment's setRetainInstance(boolean)

...you leave the Activity by pressing the back button (thus, calling finish() and effectively destroying the Activity), all of the Activitys attached Fragments will also be destroyed. Why doesn't it work with fragments on the back stack? There are probably multiple reasons why it's not supported,...
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Is a `=default` move constructor equivalent to a member-wise move constructor?

... same declared function type (except for possibly differing ref-qualifiers and except that in the case of a copy constructor or copy assignment operator, the parameter type may be “reference to non-const T”, where T is the name of the member function’s class) as if it had been implicitly decla...
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How to toggle a value in Python

What is the most efficient way to toggle between 0 and 1 ? 17 Answers 17 ...
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How do I Sort a Multidimensional Array in PHP [duplicate]

...a loaded into a multidimensional array. In this way each "row" is a record and each "column" contains the same type of data. I am using the function below to load my CSV file. ...
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Converting String to Int with Swift

The application basically calculates acceleration by inputting Initial and final velocity and time and then use a formula to calculate acceleration. However, since the values in the text boxes are string, I am unable to convert them to integers. ...