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Git: what is a dangling commit/blob and where do they come from?
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Convert column classes in data.table
...tor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(.SD, as.character), by=ID]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variabl...
How do API Keys and Secret Keys work? Would it be secure if I have to pass my API and secret keys to
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benben
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Is it possible to figure out the parameter type and return type of a lambda?
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PostgreSQL return result set as JSON array?
... an array.
SELECT json_agg(t) FROM t
There is no jsonb (introduced in 9.4) version of json_agg. You can either aggregate the rows into an array and then convert them:
SELECT to_jsonb(array_agg(t)) FROM t
or combine json_agg with a cast:
SELECT json_agg(t)::jsonb FROM t
My testing suggests t...
val-mutable versus var-immutable in Scala
...aniel C. SobralDaniel C. Sobral
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Creating range in JavaScript - strange syntax
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What do hjust and vjust do when making a plot using ggplot?
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The value of hjust and vjust are only defined between 0 and 1:
0 means left-justified
1 means ...
When to use an object instance variable versus passing an argument to the method
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answered Dec 6 '08 at 10:45
TomTom
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