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Can dplyr package be used for conditional mutating?
... ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; however, note that since if_else is stricter than ifelse (both legs of the condition must...
C-like structures in Python
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Use a named tuple, which was added to the collections module in the standard library in Python 2.6. It's also possible to use Raymond Hettinger's named tuple recipe if you need to support Python 2.4.
It's nice for your basic example, but also covers a b...
Detecting when a div's height changes using jQuery
I've got a div that contains some content that's being added and removed dynamically, so its height is changing often. I also have a div that is absolutely positioned directly underneath with javascript, so unless I can detect when the height of the div changes, I can't reposition the div below it.
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Does JavaScript have the interface type (such as Java's 'interface')?
...ld make it conform to the interface, and then undefine all the stuff that made it conform. It'd be so easy to subvert the type system -- even accidentally! -- that it wouldn't be worth it to try and make a type system in the first place.
Instead, JavaScript uses what's called duck typing. (If it w...
Should an Enum start with a 0 or a 1?
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axmrnv
75088 silver badges2121 bronze badges
answered Aug 31 '11 at 13:18
Andrey TaptunovAndrey Taptunov
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How can I use PHP to dynamically publish an ical file to be read by Google Calendar?
...oogle search on PHP ical just brings up phpicalendar and how to parse or read IN ical files. I just want to write a PHP file that pulls events from my database and writes them out in ical format.
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Font Awesome icon inside text input element
...t is not intended to work on replaced content like img and input elements. Adding a wrapping element and declare a font-family is one of the possibilities, as is using a background image. Or maybe a html5 placeholder text fits your needs:
<input name="username" placeholder="&#61447;">
B...
performSelector may cause a leak because its selector is unknown
...id *)imp;
func(_controller, selector);
Or more tersely (though hard to read & without the guard):
SEL selector = NSSelectorFromString(@"someMethod");
((void (*)(id, SEL))[_controller methodForSelector:selector])(_controller, selector);
Explanation
What's going on here is you're asking the ...
Insert line after first match using sed
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Duncan X Simpson
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answered Mar 21 '13 at 22:27
Gilles QuenotGilles Quenot
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How to make a in Bootstrap look like a normal link in nav-tabs?
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Pang
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answered Nov 14 '13 at 16:02
SW4SW4
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