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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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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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Centering text in a table in Twitter Bootstrap
... text-align is set to left, rather than center.
Adding this should center all your tds:
.table td {
text-align: center;
}
@import url('https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css');
table,
thead,
tr,
tbody,
th,
td {
text-align: center;
}
.ta...
Reading GHC Core
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GHC Core is the System FC language into which all Haskell is translated. The (approximate) grammar for Core is given by:
Core is closely related to the simpler and better known System F. All transformations GHC does on the Core level are type-preserving refactorings o...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
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@KonradGadzina: Strict equals will make all three functions return false.
– Jon
May 9 '14 at 10:18
1
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How to determine if a point is in a 2D triangle? [closed]
...uction, and division is much, much, slower. Numeric issues are also much smaller, due to no division! all calculations are exact. Thanks, Rick
– user252020
Jan 16 '10 at 4:57
4
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Get screen width and height in Android
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@EpicPandaForce actually I was thinking of Android Oreo which allows launching an activity on another display, see the following: developer.android.com/reference/android/app/…
– satur9nine
Jul 10 '18 at 2...
HAProxy redirecting http to https (ssl)
...lancing and only want my site to support https. Thus, I'd like to redirect all requests on port 80 to port 443.
15 Answers...
LINQ - Left Join, Group By, and Count
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.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
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Imitating a blink tag with CSS3 animations
I really want to make a piece of text blink the old-school style without using javascript or text-decoration.
9 Answers
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