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Is APC compatible with PHP 5.4 or PHP 5.5?
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14 Answers
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How can I get a Bootstrap column to span multiple rows?
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167
For Bootstrap 3:
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/boots...
How to sort a list in Scala by two fields?
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217
rows.sortBy(r => (r.lastName, r.firstName))
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Breaking loop when “warnings()” appear in R
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152
You can turn warnings into errors with:
options(warn=2)
Unlike warnings, errors will interr...
Transparent ARGB hex value
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edited Feb 18 '16 at 5:17
Robert
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answered Apr 2...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...
Why does direction of index matter in MongoDB?
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114
MongoDB concatenates the compound key in some way and uses it as the key in a BTree.
When fin...
C++ preprocessor __VA_ARGS__ number of arguments
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12 Answers
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promise already under evaluation: recursive default argument reference or earlier problems?
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164
Formal arguments of the form x=x cause this. Eliminating the two instances where they occur w...
sed: print only matching group
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140
Match the whole line, so add a .* at the beginning of your regex. This causes the entire line ...