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Dynamically select data frame columns using $ and a character value
...e that must first be evaluated in the second argument. You may only pass a string which is never evaluated.
Instead use [ (or [[ if you want to extract only a single column as a vector).
For example,
var <- "mpg"
#Doesn't work
mtcars$var
#These both work, but note that what they return is d...
How to get the full url in Express?
...from req.originalUrl (thanks @pgrassant). Note this DOES include the query string. docs here on req.url and req.originalUrl. Depending on what you intend to do with the URL, originalUrl may or may not be the correct value as compared to req.url.
Combine those all together to reconstruct the absolu...
How to prettyprint a JSON file?
...nting this also works without explicit parsing: print json.dumps(your_json_string, indent=4)
– Peterino
Aug 4 '14 at 14:07
11
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Define make variable at rule execution time
... tar -C $(TMP) cf $@ .
rm -rf $(TMP)
The eval function evaluates a string as if it had been typed into the makefile manually. In this case, it sets the TMP variable to the result of the shell function call.
edit (in response to comments):
To create a unique variable, you could do the follo...
How to get share counts using graph API
...hare count of an URL using PHP SDK and using the deprecated rest API, but didn't find a way to get the share counts of an URL using graph API.
...
How to disable/enable select field using jQuery?
...ould like to use code like this:
<form>
<input type="checkbox" id="pizza" name="pizza" value="yes">
<label for="pizza">I would like to order a</label>
<select id="pizza_kind" name="pizza_kind">
<option>(choose one)</option>
<option value="m...
UTF-8, UTF-16, and UTF-32
...ling. The code point is already available right there in your array/vector/string.
– richq
Jan 30 '09 at 17:48
24
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How to generate a git patch for a specific commit?
...
can you please be kind enough to provide an example for the first command
– Kasun Siyambalapitiya
Dec 14 '16 at 6:22
1
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XPath to find elements that does not have an id or class
How can I get all tr elements without id attribute?
4 Answers
4
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How do I configure Maven for offline development?
...
Also consider you can use "mvn dependency:go-offline" to ensure all the dependencies referred to in your pom.xml are present in your local repository.
– Thorbjørn Ravn Andersen
May 3 '14 at 16:0...