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Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with i...
How to slice an array in Bash
Looking the "Array" section in the bash(1) man page, I didn't find a way to slice an array.
4 Answers
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Validating IPv4 addresses with regexp
...uch luck. It seemed at one point I had had it with (25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?(\.|$)){4} , but it produces some strange results:
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What is the optimal Jewish toenail cutting algorithm?
...ule. Luckily, humans only have five toes per foot*, so there are only 5! = 120 unrestricted sequences.
Python example:
#seq is only valid when consecutive elements in the list differ by at least two.
def isValid(seq):
for i in range(len(seq)-1):
a = seq[i]
b = seq[i+1]
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What is the ultimate postal code and zip regex?
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132
There is none.
Postal/zip codes around the world don't follow a common pattern. In some count...
Pandas index column title or name
...'
In [8]: df.index.name = 'foo'
In [9]: df.index.name
Out[9]: 'foo'
In [10]: df
Out[10]:
Column 1
foo
Apples 1
Oranges 2
Puppies 3
Ducks 4
share
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How can I plot with 2 different y-axes?
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127
update: Copied material that was on the R wiki at http://rwiki.sciviews.org/doku.php?id=tips:g...
GIF Animated 扩展：可点击透明背景动画GIF播放器 · App Inventor 2 中文网
...的并支持透明背景。
包名：com.KIO4_AniGif.aix / com.KIO4_AniGif10.aix（Android 10+）
技术基础：基于 GifDecoder.java 开发，包含大量修改
最后更新：2022年6月21日
下载链接
扩展文件需从外部网站获取：
com.KIO4_AniGif.aix
p193...
Determine the data types of a data frame's columns
...se ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@...
How to compare two strings in dot separated version format in Bash?
...ny way to compare such strings on bash, e.g.: 2.4.5 and 2.8 and 2.4.5.1 ?
29 Answers
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