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How to change border color of textarea on :focus
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Assign multiple columns using := in data.table, by group
...1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello 4.5 9
# 4: 1 4 h...
How to loop through all but the last item of a list?
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edited Sep 23 '15 at 8:47
slhck
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Algorithm for Determining Tic Tac Toe Game Over
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5
I don't understand draw check at the end, shouldn't it not subtract 1?
– Inez
Jan 17 '14 at 3:08
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Mysql adding user for remote access
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edited Aug 28 '19 at 8:57
Ali Raza
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answered Apr 29 '13 at 20:58
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How do you get the width and height of a multi-dimensional array?
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answered Nov 23 '10 at 19:52
Reed CopseyReed Copsey
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What are the special dollar sign shell variables?
... harming'
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answered Mar 2 '11 at 4:04
kojirokojiro
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In CMake, how can I test if the compiler is Clang?
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regex for zip-code
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^\d{5}(?:[-\s]\d{4})?$
^ = Start of the string.
\d{5} = Match 5 digits (for condition 1, 2, 3)
(?:…) = Grouping
[-\s] = Match a space (for condition 3) or a hyphen (for condition 2)
\d{4} = Match 4 digits (for condition 2, 3...
Why does [5,6,8,7][1,2] = 8 in JavaScript?
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[1,2,3,4,5,6][1,2,3];
^ ^
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array + — array subscript access operation,
where index is `1,2,3`,
which is an expression that evaluates to `3`.
The seco...