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Extracting the last n characters from a string in R
... @mdsumner points out. Consider:
x <- c("some text in a string", "I really need to learn how to count")
substrRight(x, 6)
[1] "string" " count"
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Remove leading or trailing spaces in an entire column of data
How do I remove leading or trailing spaces of all cells in an entire column?
6 Answers
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SparseArray vs HashMap
...pe.
There are some variants for different key/value types, even though not all of them are publicly available.
Benefits are:
Allocation-free
No boxing
Drawbacks:
Generally slower, not indicated for large collections
They won't work in a non-Android project
HashMap can be replaced by the fol...
What's the correct way to communicate between controllers in AngularJS?
...ms as raised by @numan. That is because the event will bubble down through all scopes.
However, the latter (using $rootScope.$emit + $rootScope.$on) does not suffer from this and can therefore be used as a fast communication channel!
From the angular documentation of $emit:
Dispatches an even...
CSS: fixed position on x-axis but not y?
... Spent ages finding a solution for this, your answer fit my needs ideally.
– Christopher Shaw
May 3 '18 at 9:43
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What's the valid way to include an image with no src?
I have an image that I will dynamically populate with a src later with javascript but for ease I want the image tag to exist at pageload but just not display anything. I know <img src='' /> is invalid so what's the best way to do this?
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Jump to function definition in vim
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/ is almost always not precise, as it's going to match all ocurrences. I found out you can actually do :tag <function_name> to jump to the definition via ctags.
– Fuad Saud
Mar 5 '14 at 20:00
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How to get a list of repositories apt-get is checking? [closed]
...y << current.repos.list
Regarding getting repo from a package (installed or available), this will do the trick
apt-cache policy package_name |grep -m1 http| awk '{ print $2 " " $3 }'
However, that will show you the repository of the latest version available of that package, you may have m...
What's the best way of implementing a thread-safe Dictionary?
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As Peter said, you can encapsulate all of the thread safety inside the class. You will need to be careful with any events you expose or add, making sure that they get invoked outside of any locks.
public class SafeDictionary<TKey, TValue>: IDictionary&...
Difference between val() and text()
...ut element -- regardless of type. .text() gets the innerText (not HTML) of all the matched elements:
.text()
The result is a string that contains
the combined text contents of all
matched elements. This method works on
both HTML and XML documents. Cannot be
used on input elements. For i...