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List distinct values in a vector in R
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If the data is actually a factor then you can use the levels() function, e.g.
levels( data$product_code )
If it's not a factor, but it should be, you can convert it to factor first by using the factor() function, e.g.
lev...
Unable to access JSON property with “-” dash
...).
To access a key that contains characters that cannot appear in an identifier, use brackets:
jsonObj["profile-id"]
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How to find/remove unused dependencies in Gradle
... Gradle Lint plugin is a pluggable and configurable linter tool for
identifying and reporting on patterns of misuse or deprecations in
Gradle scripts and related files.
This plugin has various rules. Unused Dependency Rule is one of them. It has three specific characteristics.
Removes unused...
How can I determine whether a Java class is abstract by reflection
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It'll have abstract as one of its modifiers when you call getModifiers() on the class object.
This link should help.
Modifier.isAbstract( someClass.getModifiers() );
Also:
http://java.sun.com/javase/6/docs/api/java/lang/reflect/Modifier.html
http://java.s...
How to equalize the scales of x-axis and y-axis in Python matplotlib?
...plt.plot(range(5)) and plt.gca().set_aspect('equal', adjustable='box') do, if you don't mind? Also, I notice that even if I don't have plt.draw(), the plot will still show up. Then what is the use of it?
– Sibbs Gambling
Aug 2 '13 at 1:43
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How do I kill background processes / jobs when my shell script exits?
...mess, trap can be used. It can provide a list of stuff executed when a specific signal arrives:
trap "echo hello" SIGINT
but can also be used to execute something if the shell exits:
trap "killall background" EXIT
It's a builtin, so help trap will give you information (works with bash). If you...
CSS: How to remove pseudo elements (after, before,…)?
...ter {
content: none;
}
none is the official value to set the content, if specified, to nothing.
http://www.w3schools.com/cssref/pr_gen_content.asp
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How do I get the MIN() of two fields in Postgres?
...etails). NULL values in the list are ignored. The result will be NULL only if all the expressions evaluate to NULL.
Note that GREATEST and LEAST are not in the SQL standard, but are a common extension. Some other databases make them return NULL if any argument is NULL, rather than only when all...
Is there a way to use two CSS3 box shadows on one element?
... You're missing the spead radius btw; that can make quite a difference. Also the opacity on the shadow really can make a difference. You can play with box shadows if you open dev tools here on my blog entry. fullstack.life/css3-multiple-box-shadows.html
– fullstac...
Java OCR implementation [closed]
...gh the great work of a volunteer researcher/developer.
Give it a try, and if you don't like it, you can always improve it!
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