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Why does the JavaScript need to start with “;”?
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I would say since scripts are often concatenated and minified/compressed/sent together there's a chance the last guy had something like:
return {
'var':'value'
}
at the end of the last script without a ; on the end. If you have a ; at the start on yours, it's safe, e...
To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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Emacs: print key binding for a command or list all key bindings
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C-h f (or M-x describe-function) will show you the bindings for a command.
You are correct, C-h b (or M-x describe-bindings) will show you all bindings. C-h m (M-x describe-mode) is also handy to list bindings by mode.
You might also try C-h k (M-x describe-key) to show what command is bound ...
String to LocalDate
... Also submitted an edit for the format "yyyy-MMM-dd". YYYY is year of era, and (more egregiously) DD is day of year.
– Spencer Kormos
Jan 5 '12 at 16:55
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Android Fragments: When to use hide/show or add/remove/replace?
...longer visible. So you could technically still interact with the fragment and reattach its UI later you need to. If you replace the fragment, the you are actually pulling it out of the container and it will go through all of the teardown events in the lifecycle (onPause, onStop, etc) and if for so...
Why does Sql Server keep executing after raiserror when xact_abort is on?
...tion error - it's not.
Your workaround is just about what you need to do, and using an explicit transaction doesn't have any effect on the behavior you want to change.
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Logging framework incompatibility
I'm building a small Java app and hoping to use logback for logging.
3 Answers
3
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How to select first parent DIV using jQuery?
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parents("div") is traversing and returns all the parent div's you should use .eq(0) after it to make sure it returns just the one you want
– meo
Aug 17 '11 at 7:44
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How to add target=“_blank” to JavaScript window.location?
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@BenRacicot well yes, popups are blocked by default and most people don't change that
– twinlakes
Nov 5 '15 at 0:11
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What is the 'cls' variable used for in Python classes?
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The distinction between "self" and "cls" is defined in PEP 8 . As Adrien said, this is not a mandatory. It's a coding style. PEP 8 says:
Function and method arguments:
Always use self for the first argument to instance methods.
Always use cls for the firs...