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How can I check if character in a string is a letter? (Python)
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195
You can use str.isalpha().
For example:
s = 'a123b'
for char in s:
print(char, char.isa...
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 do I revert master branch to a tag in git?
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160
You can do
git checkout master
git reset --hard tag_ABC
git push --force origin master
Plea...
How to escape a single quote inside awk
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163
This maybe what you're looking for:
awk 'BEGIN {FS=" ";} {printf "'\''%s'\'' ", $1}'
That i...
How to write multiple line string using Bash with variables?
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kernel="2.6.39"
distro="xyz"
cat >/etc/myconfig.conf <<EOL
line 1, ${kernel}
line 2,
line 3, ${distro}
line 4 line
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EOL
cat /etc/myconfig.conf
This construction is referred to as a Here Document and can be found in the Bash man pages under man --pager='less -p "\s*Here Documents"'...
jQuery attr vs prop?
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71
Unfortunately none of your links work :(
Some insight though, attr is for all attributes. prop i...
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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162
There is a known issue with Rails 3.1.1 that breaks this functionality. If you are having this...
Getting the count of unique values in a column in bash
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153
To see a frequency count for column two (for example):
awk -F '\t' '{print $2}' * | sort | un...
What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...ic sort 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/h...