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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = dat...
How to get a substring of text?
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246
If you have your text in your_text variable, you can use:
your_text[0..29]
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Replace specific characters within strings
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With a regular expression and the function gsub():
group <- c("12357e", "12575e", "197e18", "e18947")
group
[1] "12357e" "12575e" "197e18" "e18947"
gsub("e", "", group)
[1] "12357" "12575" "19718" "18947"
What gsub does here is to replace each occurrence of "e" with an empty string ""....
How do I find the most recent git commit that modified a file?
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237
git log supports looking at the history of specific files (and directories), so you can call i...
How to fix error with xml2-config not found when installing PHP from sources?
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All you need to do instal install package libxml2-dev for example:
sudo apt-get install libxml2-dev
On CentOS/RHEL:
sudo yum install libxml2-devel
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How can I get list of values from dict?
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Yes it's the exact same thing in Python 2:
d.values()
In Python 3 (where dict.values returns a view of the dictionary’s values instead):
list(d.values())
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Nested JSON objects - do I have to use arrays for everything?
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204
You don't need to use arrays.
JSON values can be arrays, objects, or primitives (numbers or s...
Find and replace string values in list
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282
words = [w.replace('[br]', '<br />') for w in words]
These are called List Comprehensi...