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How to use a variable to specify column name in ggplot
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If for whatever reason you'd rather not use aes_string, you could change it to (the somewhat more cumbersome):
ggplot( rates.by.groups, aes(x=name, y=rate, colour= get(column),
group=get(column) ) )
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You have already activated rake 0.9.0, but your Gemfile requires rake 0.8.7
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First, check to make sure that rake is mentioned in your Gemfile. If it's not, add it, and specify the version "you already activated".
Then, you'll need to tell bundle to update the rake version it's using for your app:
bundle update rake
It'll update your Gemfile.lock for you.
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UTF-8 all the way through
...and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly use utf8mb4 encoding if a utf8mb4_* collation is specified (without any explicit character set).
In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simply utf8, which only supports a subset o...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
I have come across a situation (which I think is weird but is possibly quite normal) where I use the EntityManager.getReference(LObj.getClass(), LObj.getId()) to get a database entity and then pass the returned object to be persisted in another table.
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How to list the files inside a JAR file?
...e == null)
break;
String name = e.getName();
if (name.startsWith("path/to/your/dir/")) {
/* Do something with this entry. */
...
}
}
}
else {
/* Fail... */
}
Note that in Java 7, you can create a FileSystem from the JAR (zip) file, and then use NIO's directory wa...
Is embedding background image data into CSS as Base64 good or bad practice?
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It's not a good idea when you want your images and style information to be cached separately. Also if you encode a large image or a significant number of images in to your css file it will take the browser longer to download...
How to create a self-signed certificate with OpenSSL
...embedded Linux device. I have tried to generate a self-signed certificate with these steps:
15 Answers
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How do I disable a Pylint warning?
..."more than one statement on a single line" -- I often put if statements with short single-line results on the same line), in Pylint 0.21.1 (if it matters: astng 0.20.1, common 0.50.3, Python 2.6.6 (r266:84292, Sep 15 2010, 16:22:56)).
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Can an abstract class have a constructor?
...n the parent
abstract class, the constructor used in subclass must explicitly call
the parent constructor.
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How do I detect that an iOS app is running on a jailbroken phone?
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It depends what you mean by jailbreak. In the simple case, you should be able to see if Cydia is installed and go by that - something like
NSString *filePath = @"/Applications/Cydia.app";
if ([[NSFileManager defaultManager]...