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How to check if object (variable) is defined in R?
...eck if some variable is defined in R - without getting an error. How can I do this?
6 Answers
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Postgres unique constraint vs index
As I can understand documentation the following definitions are equivalent:
8 Answers
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Using a dispatch_once singleton model in Swift
... let" — has this been stated anywhere? I can't find mention of it in the documentation.
– jtbandes
Jun 18 '14 at 22:45
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How to check if an element is in an array
In Swift, how can I check if an element exists in an array? Xcode does not have any suggestions for contain , include , or has , and a quick search through the book turned up nothing. Any idea how to check for this? I know that there is a method find that returns the index number, but is there ...
Best way to work with transactions in MS SQL Server Management Studio
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The easisest thing to do is to wrap your code in a transaction, and then execute each batch of T-SQL code line by line.
For example,
Begin Transaction
-Do some T-SQL queries here.
Rollback transaction -- OR commit transaction
If you...
How to affect other elements when one element is hovered
What I want to do is when a certain div is hovered, it'd affect the properties of another div .
6 Answers
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Regex Email validation
... return false;
}
}
This saves you a lot af headaches because you don't have to write (or try to understand someone else's) regex.
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JQuery to load Javascript file dynamically
...y as my framework. Is there a built-in method or plugin that will help me do this?
2 Answers
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How to write to a file, using the logging Python module?
...")
self.logger = logging.getLogger('urbanGUI')
In order, the five parts do the following:
set the output file (filename=logname)
set it to append rather than overwrite (filemode='a')
determine the format of the output message (format=...)
determine the format of the output time (datefmt='%H:%M...
vertical divider between two columns in bootstrap
...using twitter bootstrap, and have a row which has two columns (span6). How do I create a vertical divider between both the spans.
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