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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)...
Why does JPA have a @Transient annotation?
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Not sure I'm understanding you, but have a look at "Pascal Thivent"'s answer ;)
– Jawher
Jan 28 '10 at 15:46
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How do detect Android Tablets in general. Useragent?
...sing a Motorola Zoom to try our tablet site testing.
The issue is that the Android Useragent is a general Useragent and there is no difference between tablet Android and mobile Android. I don't want to just target a specific device like the Xoom Useragent since Android will most likely be on multip...
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,...
grep a file, but show several surrounding lines?
... would like to grep for a string, but also show the preceding five lines and the following five lines as well as the matched line. How would I be able to do this?
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What does ':' (colon) do in JavaScript?
I'm learning JavaScript and while browsing through the jQuery library I see : (colon) being used a lot. What is this used for in JavaScript?
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How can I write text on a HTML5 canvas element?
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Is there any way to get the font width and size so we can center it? (Dynamic content)
– Oliver Dixon
Dec 30 '14 at 2:20
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GlobalConfiguration.Configure() not present after Web API 2 and .NET 4.5.1 migration
...ecently started following this guide to migrate my project to .NET 4.5.1 and Web Api 2.
11 Answers
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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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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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