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Order data frame rows according to vector with specific order
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Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target <- c("b", "c", "a", "d")
df[match(target, df$name),]
name value
2 b TRUE
3 c FALSE
1 a TRUE
4 d FALSE
It will work as long as your target contains exact...
How to remove the lines which appear on file B from another file A?
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If the files are sorted (they are in your example):
comm -23 file1 file2
-23 suppresses the lines that are in both files, or only in file 2. If the files are not sorted, pipe them through sort first...
See the man page here
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How do I execute a program using Maven?
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151
With the global configuration that you have defined for the exec-maven-plugin:
<plugin>...
How to change ViewPager's page?
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answered Sep 16 '11 at 14:40
Mark AllisonMark Allison
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What's a quick way to test to see a file exists?
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1 Answer
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How to get Scala List from Java List?
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178
EDIT: Note that this is deprecated since 2.12.0. Use JavaConverters instead. (comment by @Yaro...
How do I adjust the anchor point of a CALayer, when Auto Layout is being used?
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11 Answers
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URL query parameters to dict python
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193
Use the urllib.parse library:
>>> from urllib import parse
>>> url = "http:...
Transpose/Unzip Function (inverse of zip)?
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12 Answers
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