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How do I replace NA values with zeros in an R dataframe?
...ent in @gsk3 answer. A simple example:
> m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10 NA 2 1 7 2
3 1 1 6 3 6 NA 1 4 1 6
4 NA 4 NA 7 10 2 NA 4 ...
What are the aspect ratios for all Android phone and tablet devices?
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║ 19 x 10 ║ 0.526... ║ 1.9 ║
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Get line number while using grep
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edited May 10 at 14:10
Dominykas Mostauskis
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How to extract text from a string using sed?
...1/p'
– Kshitiz Sharma
Dec 12 '13 at 10:06
1
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Select first 4 rows of a data.frame in R
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Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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Split a vector into chunks in R
...eiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 12 4 6 8 4 2 7 6 5
[53] 4 5 4 5 5 8 7 7 7 6 2 4 3 3 8 11 6 6 1 8 4
> max <- 20
> ...
How to express infinity in Ruby?
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Dorian
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answered Apr 25 '11 at 12:31
MattMatt
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Regular expression for letters, numbers and - _
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answered Jun 12 '10 at 12:25
polygenelubricantspolygenelubricants
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Does Ruby have a string.startswith(“abc”) built in method?
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answered Nov 9 '10 at 4:48
Jörg W MittagJörg W Mittag
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All permutations of a Windows license key
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