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Creating a new column based on if-elif-else condition
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Of course, this is not vectorized so performance may not be as good when scaled to a large number of records. Still, I think it is much more readable. Especially coming from a SAS background.
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What's a standard way to do a no-op in python?
...if / elif / else constructs in python, and I want to include options which can occur, but for which the corresponding action is to do nothing. I realise I could just exclude those if statements, but for readability I find it helps to include them all, so that if you are looking through the code you ...
Python non-greedy regexes
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Wildcard characters @Trevor Boyd Smith
– Serge
Feb 24 '17 at 9:32
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:after vs. ::after
...than ::after not being supported in older browsers)? Is there any practical reason to use the newer specification?
2 Ans...
Rails migrations: self.up and self.down versus change
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For many operations rails can guess what is the inverse operation (without problems). For example, in your case what is the reverse operation of add_column to call when you rollback? Of course it's remove_column. What is the inverse of create_table? I...
Nginx not picking up site in sites-enabled?
...rch I have not figured out why this doesn't work! I am trying to move my localhost to my sites-enabled folder which is in /etc/nginx/sites-enabled/default.
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Should I use encoding declaration in Python 3?
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Because the default is UTF-8, you only need to use that declaration when you deviate from the default, or if you rely on other tools (like your IDE or text editor) to make use of that information.
In other words, as far as Pyt...
Is it possible for intellij to organize imports the same way as in Eclipse?
...ich eclipse imports is: Java, Javax, Org, Com, everything else in alphabetical order. Is it possible to configure IDEA to follow these rules?
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PHP: Count a stdClass object
...(unless it's a custom object that implements the Countable interface). Try casting the object, like below, as an array and seeing if that helps.
$total = count((array)$obj);
Simply casting an object as an array won't always work but being a simple stdClass object it should get the job done here.
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When annotating a class with @Component, does this mean it is a Spring Bean and Singleton?
... for these annotations to be detected, you need to place this line in applicationContext.xml:
<context:component-scan base-package="com.yourcompany" />
About singletons - spring beans are all in singleton scope by default. The only thing you have to have in mind is that you should not store...