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How to override trait function and call it from the overridden function?
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Maciej Pyszyński
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answered Aug 13 '12 at 17:30
ircmaxellircmaxell...
Assign multiple columns using := in data.table, by group
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This now works in v1.8.3 on R-Forge. Thanks for highlighting it!
x <- data.table(a = 1:3, b = 1:6)
f <- function(x) {list("hi", "hello")}
x[ , c("col1", "col2") := f(), by = a][]
# a b col1 col2
# 1: 1 1 hi hello
# 2: 2 2 hi hell...
How to git clone a specific tag
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Erik SaunierErik Saunier
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SQL UPDATE all values in a field with appended string CONCAT not working
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answered Nov 8 '10 at 21:46
Marc BMarc B
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C/C++ macro string concatenation
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158
If they're both strings you can just do:
#define STR3 STR1 STR2
The preprocessor automaticall...
Why are `private val` and `private final val` different?
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82
So, this is just a guess, but it was a perennial annoyance in Java that final static variables ...
How to put an image in div with CSS?
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Dany YDany Y
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What's the difference between lists enclosed by square brackets and parentheses in Python?
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278
Square brackets are lists while parentheses are tuples.
A list is mutable, meaning you can chan...
How to map and remove nil values in Ruby
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8 Answers
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How to encode the filename parameter of Content-Disposition header in HTTP?
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18 Answers
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