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Determine the number of NA values in a column
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321
You're over-thinking the problem:
sum(is.na(df$col))
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How to pick just one item from a generator?
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Everytime you would like an item, use
next(g)
(or g.next() in Python 2.5 or below).
If the generator exits, it will raise StopIteration. You can either catch this exception if necessary, or use the default argument to next():
next(g, default_value)
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TextView - setting the text size programmatically doesn't seem to work
I am using Eclipse Indigo, testing on 2 emulators(2.2 and 3.0).
7 Answers
7
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How to execute XPath one-liners from shell?
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274
You should try these tools :
xmlstarlet : can edit, select, transform... Not installed by def...
Rails 3 migrations: Adding reference column?
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205
If you are using the Rails 4.x you can now generate migrations with references, like this:
ra...
How do you write multiline strings in Go?
...e string is delimited by backticks instead of double quotes.
`line 1
line 2
line 3`
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How do I step out of a loop with Ruby Pry?
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edited May 22 '19 at 14:05
Qortex
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How to get arguments with flags in Bash
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edited Jul 24 '19 at 5:04
Pablo Bianchi
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How does LMAX's disruptor pattern work?
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211
The Google Code project does reference a technical paper on the implementation of the ring buf...
How to migrate back from initial migration in Django 1.7?
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2 Answers
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