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Convert column classes in data.table
...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 variables:
$ ID : Factor w/ 2 level...
Does SQLAlchemy have an equivalent of Django's get_or_create?
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edited Mar 17 '14 at 13:17
answered Apr 6 '10 at 17:47
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How to get folder path from file path with CMD
...ions/4451668)
– Nigel Touch
Mar 20 '14 at 15:47
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Best way to extract a subvector from a vector?
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14 Answers
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CSS background image to fit width, height should auto-scale in proportion
... got any bright ideas?
– spraff
Feb 14 '12 at 12:40
According to quirksmode.org/css/contents.html#t44 it should work i...
How to debug Google Apps Script (aka where does Logger.log log to?)
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answered Aug 7 '12 at 14:39
d0c_s4vaged0c_s4vage
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Difference between a “coroutine” and a “thread”?
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Alex MartelliAlex Martelli
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What are the differences between a clustered and a non-clustered index?
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It's purely dogma. It's not "faster to read because the data is stored in order". It's faster to read because you avoid an index read AND T...
What is a WeakHashMap and when to use it? [duplicate]
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edited Jan 1 '17 at 14:57
gstackoverflow
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Font from origin has been blocked from loading by Cross-Origin Resource Sharing policy
...the nice info!
– NineCattoRules
Apr 14 '15 at 8:56
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