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How can I check if character in a string is a letter? (Python)
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edited Jan 4 at 23:55
AMC
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answere...
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 exactly...
How do I revert master branch to a tag in git?
...igin master
– danza
Apr 11 '13 at 7:42
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How to escape a single quote inside awk
... fedorqui 'SO stop harming'
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answered Mar 28 '12 at 0:31
SteveSteve
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How to write multiple line string using Bash with variables?
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The syntax (<<<) and the command used (echo) is wrong.
Correct would be:
#!/bin/bas...
invalid multibyte char (US-ASCII) with Rails and Ruby 1.9
I'm using Ruby 1.9.1 with Rails 2.3.4 My application is to handle text input
6 Answers
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ActiveRecord, has_many :through, and Polymorphic Associations
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EmFiEmFi
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Getting the count of unique values in a column in bash
...e.Paused until further notice.
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...ort compares the numbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_...